1,1,13,3,3-Hexafluoro-2-phenyl-2-propanol

Hexafluoro-2-phenyl-2-propanol may be recovered from mother liquors, recovered solvent, and the KBr salt cake by extracting the mixture with aqueous base. Neutralization of the aqueous phase gives the alcohol (13-23 g.) which is purified by distillation. 

This dialkoxydiphenylsulfurane has been prepared by the reaction of diphenyl sulfide, 2,2,2-trifluoro-l-phenyl-l-(trifluoromethyl)ethyl hypochlorite, and potassium l,l,l,3,3,3-hexafluoro-2-phenyl-2-propanolate and by the reaction of diphenyl sulfide with 1 equivalent of chlorine and 2 equivalents of potassium 1,1,1,3,3,3-hexafluoro-2-phenyl-2-propanolate in diethyl ether. ... 

Direct formation of 5,5-dihydro-5-iminothianthrene by reaction with hydroxylamine mesitylsulfonate presumably involves, first, electrophilic amination at sulfur (74TL1973). Electrophilic S-bromination (see also Section III, A, 3, b) must be presumed to initiate the conversion of thianth-rene into the sulfurane 25 by reaction with bromine in the presence of the alcohol (RfOH = l,l,l,3,3,3-hexafluoro-2-phenyl-2-propanol) (77JOC3222). 

Potassium cyanide, 56, 20 Potassium diethyl phosphite, 58, 135, 138 Potassium 1,1,1,3,3,3-hexafluoro-2-phenyl-2 propanolate, 57, 22 Potassium iodide, 55, 71 Potassium permanganate, 55,68,58,47, 52 Potassium p-toluenesulfinate, 57, 8 /-Proline, iV-benzyloxycarbonyl-3-hy-droxy-, 56, 89... 

Preparation. The sulfurane (I) is prepared most conveniently in nearly quantitative yield by treatment of an ethereal solution of the [>ota sium salt of hexafluoro-2-phenyl-2-propanol (RfOH, prepared by the reaction of the alcohol with potassium metal) and diphenyl sulfide with chlorine at - 78°. Removal of the potassium chloride by filtration and of the ether by evaporation under vacuum leaves the white, crystalline sulfurane (I), which can be crystallized from pentane. Moisture must be avoided... 

C2eH2aFi202S, 2,2 -Bis(1,1,1,3,3,3-hexafluoro-2-hydroxy-2-propyl) 4,4 -di-t-butyl-diphenyl spirosulfurane, 40B, 369 C26H2ftFi203S, 2,2 -Bis(1,1,1,3,3,3-hexafluoro-2-hydroxy-2-propyl)-4,4 -di-t-butyl-diphenyl spirosulfurane oxide, 40B, 369 C28H1gFiBO3S, 1,1-Bis[1,1,1,3,3,3-hexafluoro-2-phenyl-2-propanol-ato] 5-methyl-3,3 bis(trifluoromethyl)[3H-2,1-benzoxathiole], 45B, 443... 

To a stirred solution of the aromatic substrate (13.8 mg, 0.1 mmol) and the fi-dicarbonyl compound (6.6 mg, 0.5 mmol) in hexafluoro-2-propanol (0.5 ml) was added BTI (43 mg, 0.1 mmol) at room temperature under nitrogen. The reaction mixture was stirred for 15 min and then concentrated the residue was purified by column chromatography (silica gel, hexane-ethyl acetate) to give 2-(2,5-dimethoxy-phenyl)-2-methyl-l,3-cyclopentanedione (16.5 mg, 66%), m.p. 165-166°C. 

When I-halo-5-decynes are electrolyzed at carbon in DMF containing tetraalkylam-monium perchlorates [114], the yield of pentylidenecyclopentane increases dramatically (up to 60%) two other major products are 5-decyne and l-decen-5-yne. Reduction of 6-iodo-1-phenyl-1-hexyne at carbon in DMF containing TMAP affords benzylidenecyclopentane (36%) and 1-phenyl-1-hexyne (38%) however, in the presence of an added proton donor (l,l,l,3,3,3-hexafluoro-2-propanol), the yield of benzylidenecyclopentane climbs to approximately 60% [115]. 

Ethyl phenyl sulfide can be oxidized to the sulfoxide in 97% yield using 30% aqueous hydrogen peroxide in l,l,l,3,3,3-hexafluoro-2-propanol.239 No sulfone is formed. The fluorinated alcohol (bp 59°C) is recovered by distillation for use in the next run. 

Propanole 2-(4-Fluoro-phenyl)-hexafluoro- ElOa, 329 (Educt) ElOb,. 85 (Educt)... 

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