Phenyl sulfone derivative synthesis

The alkylation of the a-lithio-a-(methylsulfanyl) phenyl sulfone derived from compound 411 with a chiral epoxide has been used for the synthesis of 2-deoxynucleosides626. In the case of the starting material 416, the epoxide 417 was employed as electrophile in... 

The synthetic procedure developed for the preparation of active fonns of vitamin D analogues was applied to the synthesis of various natural steroids by the reaction of steroid moieties with phenyl sulfone derivatives described here. 

Thiazoles, vinyl-radical polymerization, 6, 278 Thiazole-5-sulfonic acid, 2-amino-synthesis, 6, 255-256 Thiazole-2-sulfonic acids reactions, 5, 104 6, 291 Thiazole-5-sulfonic acids synthesis, 6, 255 Thiazole-5-thione, 2-phenyl-tautomerism, 6, 249 Thiazolethiones reactivity, 6, 250 Thi azole-2-thiones reactions, 5, 102 tautomerism, 5, 367 Thiazolidine, 2-alkyl-occurrence, 6, 327 Thiazolidine, 2-arylimino-X-ray analysis, 6, 238 Thiazolidine, 4-imino-mesoionic didehydro derivative nomenclature, 1, 34 nomenclature, 1, 34... 

The reaction of the stabilized carbanion derived from a-phenylselanylmethyl phenyl sulfone with an acylsilane allowed the synthesis of E/Z mixtures of... 

Sulfonate groups can also be introduced during the course of the diphosphine synthesis. For example, as shown in Scheme 1, the surfactant sulfonate derivative of bis(diphenylphosphino)pentane is formed by reaction of Li P[C6H4(CH2)3C6H5]2 with (R,R)-2,4-pentanediylditosylate and subsequent sulfonation with sulfuric acid [10]. Here, the phenyl group that is not attached directly to phosphorus is less deactivated for sulfonation. 

The reaction between a carbanion derived from alkyl 3,5-bis(trifluoromethyl)phenyl sulfones and aldehydes affords, with good yields and stereoselectivities, the corresponding 1,2-disubstituted alkene through the Julia-Kocienski olefination reaction. This one-pot protocol can be performed using the phosphazene base at —78 °C and has been successfully used in a high yielding and stereoselective synthesis of various stilbenes such as resveratrol [47] (Scheme 5.28). 

Introduction of arylsulfonylmethyl substituents into nitroheteroaromatic rings is of great practical value because these sulfones are versatile intermediates in organic synthesis. Nitrobenzyl aryl sulfones and their heterocyclic analogues can easily be transformed into the corresponding ethenyl derivatives by a simple alkylation with simultaneous elimination of arylsulfinate anion [125]. Diethyl methylenemalonate substituent can be introduced in the positimi 4- of 5-nitroimidazole via the VNS reaction of 5-nitroimidazole with the carbanion of chloromethyl phenyl sulfone [112, 124], followed by condensation of the obtained 4-(phenylsulfonyl)methyl derivative with diethyl bromomalonate or diethyl ketomalonate (Scheme 33) [126]. 

Auxiliary Synthesis Both the (S)- and (R)- enantiomers of the camphor-derived ACC 54 are available in seven steps from commercially available and inexpensive (S)- and (R)-camphor sulfonic acid, respectively (Scheme 7.9). The seven-step process provides an overall yield of approximately 40%. A key step in the synthesis of 54 and 55 is the direct A -amination of the corresponding oxazolidinones, 61 and 62. This transformation is effectively achieved in a straightforward manner using a modification of a procedure recently reported by Hynes et al. ° Application of this amination procedure to commercially available (R)- or (5)-4-benzyloxazolidinone ((R)-62 or (S)-62, respectively) provides phenyl alanine-derived auxiliaries (R)-55 or (S)-55 in excellent yield. 

Stereoselective addition of methylcuprate to enantiomeri-cally pure y-hydroxy-a,p-unsaturated phenyl sulfones 101 and the conversion of the adduct 102 into carbaldehyde intermediates 104 via 103 has permitted the iterative synthesis of polypropionates stereotetrads 106 as shown in Scheme 22.29. Polypropionate stereotetrads have also been obtained through stereoselective additions of methylcuprate to 2-benzenesulfonyl-7-oxanorbom-2-ene derivatives. ... 

Ghosh AK, Zajc B. Fluorinated l-phenyl-l/7-tetrazol-5-yl sulfone derivatives as general reagents for fluoroalkylidene synthesis. J. Org. Chem. 2009 74(22) 8531-8540. 

Only a few practical applications of [ C]methyl phenyl sulfone have been reported so far (Figure 5.66). Representative ones illustrating the breadth of utility include reaction with allylic acetate in the presence of Pd(0) to give the respective 8,y-unsaturated derivative 244 as demonstrated with the synthesis of245 with ester 246 to furnish [ Cjmethyl ketone 24y203b sequential reaction of the dianion with a carbamate 12481 and an alkyl... 

M. Shi and Y.-L. Shi reported the synthesis and application of new bifunctional axially chiral (thio) urea-phosphine organocatalysts in the asymmetric aza-Morita-Baylis-Hillman (MBH) reaction [176, 177] of N-sulfonated imines with methyl vinyl ketone (MVK), phenyl vinyl ketone (PVK), ethyl vinyl ketone (EVK) or acrolein [316]. The design of the catalyst structure is based on axially chiral BINOL-derived phosphines [317, 318] that have already been successfully utilized as bifunctional catalysts in asymmetric aza-MBH reactions. The formal replacement of the hydrogen-bonding phenol group with a (thio)urea functionality led to catalysts 166-168 (Figure 6.51). 

One Sanofi synthesis of enantiomerically pure (-i-)-clopidogrel (2) utilized optically pure (R)-(2-chloro-phenyl)-hydroxy-acetic acid (20), a mandelic acid derivative, available from a chiral pool. After formation of methyl ester 21, tosylation of (/ )-21 using toluene sulfonyl chloride led to a-tolenesulfonate ester 22. Subsequently, the Sn2 displacement of 22 with thieno[3,2-c]pyridine (8) then constructed (-i-)-clopidogrel (2). Another Sanofi synthesis of enantiomerically pure (-i-)-clopidogrel (2) took advantage of resolution of racemic a-amino acid 23 to access (S)-23. The methyl ester 24 was prepared by treatment of (S)-23 with thionyl chloride and methanol. Subsequent Sn2 displacement of (2-thienyl)-ethyl para-toluene-sulfonate (25) assembled amine 26. 

Many works on the synthesis of cyclic polymers and block copolymers using kinetically controlled ring-expansion polymerizations of cyclic monomers, such as lactones and lactides with various types of cyclic tin initiators, were reviewed by Kricheldorf [147,148]. Kricheldorfs group continued the synthesis of cyclic polymers, and their recent works have focused on the following. Polycondensations of 4,4/-difluorodiphenylsulfone with tris(4-hydroxy phenyl)ethane were performed in DMSO to give multi-cyclic poly(ether sulfone)s derived from tris(4-hydroxyphenyl)ethane [149]. 

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