Which of the Following Compounds Can Have Stereoisomers?

Stereoisomer

173,176 Both stereoisomers are formed if the methylselenoalkenyllithium is hydrolyzed176 or reacted176 with an aldehyde or a ketone, whereas simply one stereoisomer of an α,β-unsaturated carbonyl compound is found from i-methylseleno-one-alkenyllithiums and DMF176 and from the 1-phenylseleno-1-alkenyllithiums and phenacyl bromide.

From: Comprehensive Organic Synthesis , 1991

Separations and Analysis

T.J. Wenzel , in Comprehensive Chirality, 2012

Glossary

Atropisomer

Stereoisomers that result from hindered rotation most a single bond.

Chiral derivatizing agent

Chiral reagent that reacts with a compound to form a covalent bail.

Chiral solvating agent

Chiral reagent that associates with a compound through non-covalent interactions.

Diastereomers

Stereoisomers that are non enantiomers or mirror images of each other and accept different reactivity and physical backdrop.

Diastereotopic groups

Two groups in a molecule that are unlike and, if replaced, generate compounds that are stereoisomers.

Dipolar coupling

A magnetic interaction that arises betwixt two particles such as hydrogen nuclei with not-zero spin.

Kinetic resolution

When two enantiomers take unlike rates of reaction.

Prochiral

Refers to molecules that can be converted from achiral to chiral in a unmarried pace.

Quadrupolar coupling

An interaction that occurs in nuclei with more than two dissimilar spin states (I>½).

Rest dipolar coupling

A weak form of dipolar coupling that occurs in partially oriented media.

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Organic Chemical Systems, Theory

Josef Michl , in Encyclopedia of Physical Science and Technology (Tertiary Edition), 2003

I.D.2 Stereoisomers

Stereoisomers have the same connectivity but differ in the way in which the elective atoms are oriented in space. They tin can be divided into configurational stereoisomers and conformational stereoisomers. The precise specification of the spatial arrangement of the groups in a configurational isomer is called its configuration, and in a conformational isomer, its conformation.

I.D.2.a Configurational stereoisomers

These stereoisomers cannot be made superimposable by whatever rotations about single bonds. In order to make them superimposable, rotation near a double bond or a dissociation of one or more than single bonds, or both, is necessary (e.grand., vi and 8 ). Since these processes normally require considerable energy, they usually do non occur at a measurable rate at room temperature. Configurational stereoisomers tin normally be isolated from one another and stored essentially indefinitely at room temperature.

I.D.ii.b Conformational stereoisomers

Oft called conformers for short, these stereoisomers can exist made superimposable by rotations about single bonds. Examples are the axial (21) and equatorial(22) conformers of a monosubstituted

21

22

cyclohexane. Since rotations about single bonds are ordinarily very facile, it is usually impossible to separate conformers from 1 another and to handle them separately at room temperature.

I.D.2.c Chirality

Another important classification of stereoisomers into 2 groups is related to optical activity, manifested by the rotation of a plane of polarized calorie-free on passage through a sample.

A pair of stereoisomers that are related to i another in the same manner as an object and its mirror image are called enantiomers (e.g., 23 and 24 ):

23

24

Any pair of stereoisomers that are not related in this style are called diastereomers (e.g., 6 and eight or 21 and 22 ).

A molecule that is not identical with its mirror image is chosen chiral and occurs as a pair of enantiomers. The necessary and sufficient condition for chirality is the absence of an improper rotational axis of symmetry in the molecule (this includes a heart of inversion and mirror plane symmetry elements).

A mixture of equal amounts of two enantiomers is known every bit a racemic modification and is optically inactive. A pure enantiomer or an unbalanced mixture of two enantiomers is optically active; the two enantiomers take opposite handedness and cause the airplane of polarization to rotate in opposite directions.

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ADME-Tox Approaches

E.H. Kerns , Fifty. Di , in Comprehensive Medicinal Chemical science II, 2007

5.20.2.2.4 Stereochemical conversion

Stereoisomers having instability at a stereogenic eye tin react to produce stereochemically modified forms. ^15–18 This tin exist triggered by an adjacent grouping that decreases stability at the chiral eye. ¹⁵ An enantiomer can irreversibly 'racemize' and accomplish the racemic mixture at equilibrium. It can also 'enantiomerize,' or reversibly interconvert to the other enantiomer. Diastereomers tin can 'diastereomerize' or 'epimerize' by conversion of an unstable stereogenic center. For case, paclitaxel (I) epimerizes in organic solutions nether basic conditions at the 7 position (2) in addition to other decomposition reactions (Figure 6). ^nineteen Thalidomide enantiomerizes at bones pHs and in solution with human serum albumin (likely due to catalysis by Arg and Lys residues). ¹⁸

Effigy six. Base induced degradation of paclitaxel (I) in methanol to 7-epipaclitaxel (Ii), 10-deacetyl paclitaxel (Iii), baccatin Iii (IV), and side chain methyl ester (V). ¹⁹

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Separation of Stereoisomers

C.Grand. Galea , ... D. Mangelings , in Supercritical Fluid Chromatography, 2017

Abstruse

Stereoisomers are isomeric molecules that have the same molecular constitution, simply a different three-dimensional spatial system of the atoms. These could be broadly classified as enantiomers and diastereomers. Unlike enantiomers bind to dissimilar receptors and possibly bring near different reactions. For this reason, stereoselective separation methods are valuable tools in the pharmaceutical, food, and agricultural fields. Liquid chromatography and supercritical fluid chromatography are the almost popular techniques used for chiral separations. This chapter presents an overview of the different chromatographic parameters that are important when developing a chiral method in SFC. Different stationary phases and their backdrop are described and a comparison of SFC with other techniques, also suitable for enantioselective separations, is made. An overview of applications in the pharmaceutical, agricultural, and food industries, using SFC, from the last 10 years is presented. Diastereomers can be separated using classical separation methods, and a brief mention of these applications is also made.

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Stereochemistry

Robert J. Ouellette , J. David Rawn , in Organic Chemistry Study Guide, 2015

Keys to the Chapter

8.1 Configuration of Molecules

Stereoisomers have different configurations. The term "configuration" refers to the arrangement of atoms in space. Geometric isomers, which nosotros previously studied in cycloalkanes and alkenes, are besides stereoisomers.

viii.two Mirror Images and Chirality

Some molecules have mirror images that are non superimposable. Such molecules are chiral. Molecules that have a plane of symmetry are achiral; they are superimposable on their mirror image.

A stereogenic center in an organic molecule is a carbon atom bonded to four different atoms or groups of atoms. Information technology is as well called a chiral center. Past inspecting the atoms or groups of atoms bonded to each carbon cantlet in a molecule, nosotros tin can easily identify any chiral centers. If a carbon cantlet is bonded to two or more than identical atoms or groups, such as two hydrogen atoms or two methyl groups, it is non a chiral center. If a carbon cantlet is bonded to 4 different atoms or groups, it is a chiral heart, and the molecule has a nonsuperimposable mirror image. The 2 possible isomers having different configurations at a chiral centre are enantiomers.

Some other way to identify a molecule every bit chiral or achiral is to look for a plane of symmetry. A plane of symmetry tin can bisect atoms, groups of atoms, and bonds betwixt atoms. In a molecule with a aeroplane of symmetry, ane side of the molecule is the mirror image of the other side. Thus, a molecule with a aeroplane of symmetry is achiral. If a molecule contains ii or more than chiral centers and does non have a plane of symmetry, it is chiral. If is has a plane of symmetry, it is an achiral meso compound.

Pairs of enantiomers have the same physical properties but behave differently in a chiral environment such as a chiral binding site in an enzyme. Nearly of the molecules isolated from living organisms are chiral. They generate a chiral environment that allows distinctions to exist made between enantiomers.

8.iii Optical Activity

Each member of a pair of enantiomers rotates the plane of polarized calorie-free in an instrument called a polarimeter. This phenomenon is called optical action. The rotation observed for 1 enantiomer is equal in magnitude but reverse in management for the other enantiomer. A chiral substance that rotates plane-polarized light clockwise is dextrorotatory; a chiral substance that rotates airplane-polarized low-cal counterclockwise is levorotatory. The amount of rotation under divers standard experimental conditions is the specific rotation. Optical purity is a measure out of the excess of i enantiomer over some other in a mixture.

eight.iv Fischer projection Formulas

Enantiomers in a Fischer projection are drawn according to the following conventions:

1.

Arrange the carbon chain vertically with the most oxidized group (—CHO in glyceraldehyde) at the "top."

2.

Place the carbon atom at the chiral center in the plane of the paper. It is C-ii in glyceraldehyde.

iii.

C-2 is bonded to four groups, the CHO grouping and the CH₂OH group extend behind the airplane of the folio, and the hydrogen atom and the hydroxyl group extend up and out of the plane.

4.

Project these four groups onto a aeroplane. The carbon atom at the chiral center usually non shown in this convention. Information technology is located at the point where the bail lines cross. The vertical lines projection abroad from the viewer. The horizontal lines project toward the viewer.

eight.5 Absolute Configuration

The Kahn–Ingold–Prelog configurational nomenclature system, which is the aforementioned for both Due east,Z geometric isomers and chiral molecules, gives an unambiguous description of the absolute configuration of a molecule.

Priority is assigned to atoms based on the diminutive numbers of direct bonded atoms. Atoms farther down the chain are ignored even though they may accept still higher atomic numbers. Thus, a fluorine atom has a higher priority than a carbon atom fifty-fifty if that carbon cantlet is bonded to three chlorine atoms; for example, F— > —CCl₃. The chlorine atoms in this instance are irrelevant because the comparing is between the atomic numbers of fluorine and carbon.

Once the priority order of the atoms or groups of atoms bonded to the chiral carbon atom has been determined, the molecule is viewed through the bond to the everyman priority group. The other three groups so lie on a circle. If the motility from priorities 1 → 2 → iii is clockwise, the molecule is R; if the motion is counterclockwise, the configuration is Southward.

The assignment of R or South configuration to a chemical compound does not identify its optical rotation as existence either (+) or (−). The management of optical rotation is experimentally determined with a polarimeter. The accented configuration is experimentally adamant by X-ray crystallography.

eight.vi Molecules with Two or More Stereogenic Centers

Some molecules have two or more stereogenic centers. The resulting stereochemistry depends on whether those centers are equivalent or nonequivalent. Equivalent sterogenic centers have identical sets of substituents. For north nonequivalent centers, in that location are ii ⁿ stereoisomers. Some of those isomers are pairs of enantiomers. These stereoisomers have opposite configurations at every center and are thus mirror images. All other stereoisomers are termed diastereomers.

The configuration of each stereogenic center is determined independently. Then, the configuration of each centre is written equally R or S. For example, the enantiomer of a molecule with a stereogenic eye 2S,3R is 2R,3Southward. Whatever other combination—iiSouthward,3S or 2R,3R— is a diastereomer.

Compounds with two or more equivalent stereogenic centers have fewer stereoisomers than predicted by the ii ^northward formula. Some of the stereoisomers have a aeroplane of symmetry and are not optically agile; they are meso compounds. For ii chiral centers, the configurations are R,Southward, which is the same equally Due south,R because of the plane of symmetry. The isomers R,R and South,S are optically active and are enantiomers.

8.vii Cyclic Compounds with Stereogenic Centers

Cyclic compounds tin accept stereogenic centers. We employ the aforementioned rules to assign configuration to circadian compounds and acyclic compounds. The only difference is that we somewhen return to the stereogenic centre every bit nosotros move around the ring. All the same, in a chiral compound, the point of first difference is reached before that time.

Cyclic compounds having ii nonequivalent stereogenic centers tin can exist in four stereoisomeric forms. An interesting feature of these molecules is seen when at that place are equivalent stereogenic centers. In those cases, in that location is at least one plane of symmetry. That airplane, in some cases, bisects bonds, and in other cases bisects the atoms of the ring. In this latter case, information technology also bisects the atoms bonded to the stereogenic centers.

8.8 Separation of Enantiomers

Enantiomers have the same physical properties and, therefore, cannot be separated by concrete methods. Even so, diastereomers take unlike physical properties and can be separated. Figure eight.18 illustrates the conversion of a mixture of enantiomers into a mixture of diastereomers. The diastereomers are separated, later which they are broken down to obtain one enantiomer from one diastereomer and the other enantiomer from the second diastereomer. Chiral chromatography provides a style to separate enantiomers based upon their diastereomeric interactions with a chiral column support.

8.9 Reactions at Stereogenic Centers

If a reaction at a stereogenic middle does not alter the bonds to the stereogenic middle, and then the configuration at that centre is unchanged.

Reactions at the stereogenic center impact the configuration of the molecule. If the production has a configuration opposite that of the reactant, we postulate a transition country in which the nucleophile attacks opposite the bond to the leaving group and inverts the configuration as the reaction occurs.

Radical reactions proceed through a planar intermediate, which is achiral. Thus, subsequent reaction with another radical tin occur with equal probability from either side of the plane of the molecule. The consequence is a racemic mixture.

8.10 Formation of Compounds with Stereogenic Centers

Germination of compounds with one stereogenic centre from achiral compounds using achiral reagents cannot yield a unmarried stereoisomer. However, in an enzyme catalyzed process, the reaction of an achiral compound generates a single stereoisomer. Such reactions are stereospecific.

In some reactions where ii stereogenic centers are generated from an achiral substrate, some mechanistic information is obtained based on the diastereomers formed. For example, the formation of two equivalent centers might give a mixture of the R,R chemical compound and the S,Due south chemical compound. Although not optically agile, that result is different than a procedure that gives the R,S (meso) compound.

8.11 Reactions that Form Diastereomers

If a new stereogenic center is generated in a reaction of a substrate that already has a stereogenic centre, then a mixture of diastereomers results. The amounts of these isomers are not equal because the new middle is generated in a chiral environment. The excess of one diastereomer over another is called the stereoselectivity of the reaction.

8.12 Prochiral Centers

In a chiral environment, two apparently equivalent groups can be distinguished, and the resulting production of a reaction involving those groups is chiral. The atomic heart at which optical activity may result is prochiral. The equivalent groups bonded to the prochiral middle are enantiotopic and are designated pro-R or pro-S to signal the potential configuration, R or Due south, if the group is replaced.

Groups at a prochiral center in a molecule that contains a chiral centre are diastereotopic. The "faces" of a planar site or functional group that contains a centre that can exist converted into a stereogenic center are designated as re or si depending on the priority ranking of the three groups and their organisation using the R,S rules.

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Soman

Harry Salem , Frederick R. Sidell , in Encyclopedia of Toxicology (Second Edition), 2005

Brute Toxicity

The stereoisomers of soman take different median lethal doses. The C(+)P(+) soman and the C(−)P(+) soman are the least toxic and subcutaneous LD ₅₀ values ⩾5000 and ⩾2000   μg   kg^−one, respectively. The more toxic stereoisomers, C(−)P(−) soman and C(+)P(−) soman, have subcutaneous LD₅₀ values of 38 and 99   μg   kg⁻¹, respectively. The racemic mixture of soman has a subcutaneous LD₅₀ of 156   μg   kg^−one in mice.

The cause of death is attributed to anoxia resulting from a combination of central respiratory paralysis, severe bronchoconstriction, and weakness or paralysis of the accessory muscles for respiration.

Signs of nervus amanuensis toxicity vary in rapidity of onset, severity, and elapsing of exposure. These are dependent on the specific agent, route of exposure, and dose. At the higher doses, convulsions and seizures indicate CNS toxicity.

Following nerve agent exposure, animals exhibit hypothermia resulting from the cholinergic activation of the hypothalamic thermoregulatory center. In addition, plasma concentrations of pituitary, gonadal, thyroid, and adrenal hormones are increased during organophosphate intoxication.

An LCt_fifty of thirty   mg   min   m⁻³ was reported in rats following a 30-min inhalation exposure to soman. The acute toxicities by other routes of exposure in various animal species are presented in Tabular array 1.

Table 1. Acute toxicities of soman in various species by various routes of exposure

Route of exposure/species	LD50 (μg   kg−1)
Percutaneous
Rat	7800
Subcutaneous
Chicken	50
Dog	12
Republic of guinea hog	24
Monkey	13
Rabbit	20
Mouse	10
Rat	71
Intramuscular
Monkey	ix.v
Mouse	89
Rat	62
Intraperitoneal
Chicken	71
Frog	251
Mouse	393
Rat	98
Intravenous
Cat	fifteen
Rat	44.5
Mouse	35

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Configurational analysis

Anil V. Karnik , Mohammed Hasan , in Stereochemistry, 2021

5.8 Chemical method

If stereoisomers have two suitable functional groups in proximity to each other, they may undergo a reaction to form a new compound, helping in assignment of relative configuration to two diastereoisomers. One such method was demonstrated by Freudenberg, for distinguishing betwixt two diastereomers of dihydroshikimic acid (please run into Fig. 5.5), which has been discussed earlier.

For circadian-one,ii-diols, the reaction of periodic acid or lead tetraacetate causing C–C bond cleavage shows a departure in rates for the cis-1,2-diols and for the trans-i,ii-diols for modest and normal ring cycloalkanes. The rates will be higher for the cis isomers and in some instances the trans isomer may not undergo the reaction. Fig. v.54 illustrates the application. Such correlations depend on type of functional groups present in the diastereomers and many possibilities exist for awarding of this methodology.

Figure five.54. Chemical method to distinguish between diastereomers.

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Stereochemistry

Robert J. Ouellette , J. David Rawn , in Principles of Organic Chemistry, 2015

Mirror Paradigm Isomers Are Enantiomers

Two stereoisomers related as nonsuperimposable mirror images are called enantiomers (Greek enantios, opposite   + meros, function). We can tell that a substance is chiral and predict that two enantiomers be by identifying the substituents on each carbon atom. A carbon atom with four unlike substituents is a stereogenic center, and a molecule with a stereogenic heart is chiral. It tin exist every bit either of a pair of enantiomers. For case, 2-bromobutane is chiral because C-two is fastened to four different groups (CH₃–, CH₃CH₂–, Br–, and H–). In contrast, no carbon in 2-bromopropane is bonded to iv different groups; C-ii is bonded to 2 methyl groups. Thus, two-bromopropane is non chiral.

Problem 6.1

Phenytoin has anticonvulsant activity. Is phenytoin chiral or achiral? Determine your answer by identifying the number of different groups bonded to its tetrahedral carbon atoms; so determine whether or not it has a plane of symmetry.

Solution

Phenytoin has but 1 sp³-hybridized carbon cantlet. Information technology is bonded to a nitrogen cantlet, a carbonyl group, and two phenyl groups. Because the sp³-hybridized carbon atom is attached to two identical phenyl groups, it is not a stereogenic heart, and as a result the molecule is achiral. Phenytoin has a plane of symmetry that lies in the plane of the page. The phenyl groups of phenytoin lie above and below the symmetry plane. Note that the other atoms of phenytoin are bisected by this plane.

Problem 6.two

The structure of nicotine is shown below. Is nicotine chiral?

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Stereochemistry

Robert J. Ouellette , J. David Rawn , in Organic Chemical science (Second Edition), 2018

Mirror Image Isomers

Two stereoisomers related equally nonsuperimposable mirror images are called enantiomers (Greek enantios, opposite + meros, part). We tin can tell that a substance is chiral and predict that ii enantiomers be by identifying the substituents on each carbon atom. A carbon cantlet with four dissimilar substituents has a stereogenic heart, and a molecule with a stereogenic centre is chiral. It tin can exist as a pair of enantiomers. For instance, ii-bromobutane is chiral because C-2 is attached to iv dissimilar groups (CH₃—CH₃CH_ii—Br— and H—). In contrast, no carbon in two-bromopropane is bonded to four different groups; and C-2 is bonded to two methyl groups. Thus, two-bromopropane is non chiral (Figures eight.4 and 8.5).

Figure viii.4. Planes of Symmetry in Dichloromethane

Dichloromethane, which has not one, but two planes of symmetry, can be superimposed on its mirror image. It is achiral.

Effigy 8.v. Airplane of Symmetry in Bromochloromethane

Bromochloromethane has a airplane of symmetry, and therefore, can exist superimposed on its mirror image. It is achiral.

The existence of a stereogenic center in a complex molecule may not exist immediately apparent. This situation occurs when the groups bonded to a chiral carbon cantlet differ at sites not immediately side by side to the stereogenic heart. The deviation between a methyl group and an ethyl group is readily apparent in 2-bromobutane. However, in some molecules, the difference is less obvious. For case, v-bromodecane and five-bromo-one-nonene both accept a stereogenic center.

Trouble 8.one

Which of the following molecules are chiral? Explain your answer.

(a)

(b)

(c)

Trouble 8.2

The structure of nicotine is shown below. Is nicotine chiral?

Problem 8.3

Phenytoin has anticonvulsant activity. Is phenytoin chiral or achiral? Determine your answer past identifying the number of unlike groups bonded to its tetrahedral carbon atoms; then determine whether or not information technology has a plane of symmetry.

Sample Solution

Phenytoin does not contain a carbon bonded to four different groups. A plane of symmetry that bisects the two phenyl groups. Ane of the benzene rings of phenytoin is in a higher place and the other below the symmetry aeroplane. It is achiral.

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Synthesis: Carbon With Iii or 4 Fastened Heteroatoms

A. Senning , J.Ø. Madsen , in Comprehensive Organic Functional Grouping Transformations 2, 2005

vi.07.2.1.2.(three) Trihalomethyl sulfoxides and trihalomethyl sulfones, CHal_threeS(O)_northwardR

While the oxidation of 1,ii-bis[(trifluoromethyl)sulfanyl]benzene 1,two-(CF_threeS)₂C₆H₄ to the corresponding bissulfoxide 1,2-[CF₃S(O)]₂C₆H_iv is readily accomplished with MCPBA the respective oxidation of the 1,4-isomer apparently requires a different oxidant, i.e., SELECTFLUOR, [i-(chloromethyl)-iv-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate)], a source of electrophilic fluorine <2001USP6215021>.

The insecticidal GABA-gated chloride aqueduct blocker fipronil, 5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-iv-[(trifluoromethyl)sulfinyl]-iH-pyrazole-3-carbonitrile 14 is an important commercial trifluoromethyl sulfoxide. Its industrial preparation by oxidation of the respective sulfide with trifluoroperacetic acid CF₃CO₃H has been fine tuned <2001WOP0130760>. 5-Amino-3-methyl-i-phenylpyrazole can be trifluoromethylsulfinylated in the 4-position by treatment with N-[(trifluoromethyl)sulfinyl]succinimide which in turn is obtained from N-lithiosuccinimide and CF₃S(O)Cl <2003EUP1331222>.

Protonated trifluoromethanesulfinic acrid [CF_iiiSO₂H_two]⁺ appears to be the reactive species in the CF₃SO₂Na(Chiliad)CF₃And so₃H mixture which converts arenes ArH with o,p-directing substituents to the respective sulfoxides CF₃Due south(O)Ar with predominant p-substitution. Yields range from 55% to 82%. In the absence of activating substituents in the substrate, i.due east., with benzene, but 24% yield can be achieved. With CF₃OPh equally ArH only ane product, i,four-(CF_threeO)C₆H_four[S(O)CF_three] is formed <2001SL550>. i-Methylpyrrole could be trifluoromethylsulfinylated in the ii-position with an in situ reagent [equivalent to [CF₃Due south(O)]⁺] prepared from CF_threeSO₂Na and Cl₃P(O) <1999T7243>.

Trimethyl(trifluoromethyl)silane CF₃SiMe₃, in the presence of catalytic amounts of TBAF, neatly reacts with arenesulfinyl chlorides ArS(O)Cl to grade the corresponding trifluoromethyl sulfoxides CF₃Southward(O)Ar (53–61% yield) <1995JFC(lxx)255>.

Tolyl trifluoromethyl sulfone CF₃S(O)_twoC_viH_fourMe-4 has been prepared in 83% yield from four-MeC₆H_fourS(O)₂F, CF₃SiMe₃, and TASF <1995JFC(lxx)255>. Contrary to all other (mostly aromatic) sulfides tested, oxidation of phenyl trifluoromethyl sulfide CF₃SPh with methyl(trifluoromethyl)dioxirane Me(CF_three)CO₂ is >99% selective towards the formation of the corresponding sulfoxide CF₃S(O)Ph and no trace of the sulfone is formed <2002JA9154>.

Bis(trifluoromethyl) sulfoxide CF_threeS(O)CF₃ and phenyl trifluoromethyl sulfoxide CF₃Southward(O)Ph have been prepared by reaction of dimethyl sulfite (MeO)₂Southward(O) and methyl benzenesulfinate PhS(O)OMe, respectively, with CsF and CF_iiiSiMe₃ <1999JOC2873>. Dichlorofluoromethyl phenyl sulfone (CCl₂F)South(O)_iiPh is the major product (xc% yield) of the oxidation of the sulfide (CCl₂F)SPh with excess H₂O₂ in AcOH with the respective sulfoxide (CCl_iiF)South(O)Ph equally the minor product (5% yield) <2001JOC643>.

Methyl methanesulfonate MeS(O)₂OMe and methyl benzenesulfonate PhS(O)_twoOMe, give methyl trifluoromethyl sulfone CF₃Southward(O)₂Me and phenyl trifluoromethyl sulfone CF₃S(O)₂Ph, respectively, when treated with CsF and CF_threeSiMe_three <1999JOC2873>. The extremely volatile sulfone [CF₃S(O)₂]₃CF has been made from the corresponding lithium common salt [CF₃South(O)_two]₃CLi and F_ii. Contrary to expectation, it does not constitute a source of F⁺ <2003JFC(122)233>.

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