Mislow

MISLOW BRAVERMAN EVANS Rearrangemenl Reversible 2.3- sigmatiopic rearrangement o( aHyUc sulloxides to ailyl suVenates which are cleaved by phosphites to allyUc alcohols. 

Mislow, K. Introduction to Stereochemistry, Benjamin Press New York, 1965, p. 131. 

Racemic [l-(4-methylphenylsulfinyl)-2-propenyl]lithium, prepared with lithium diiso-propylamide in THF, adds to racemic chiral 2-methylalkanals with good a- and syn selectivity114, us Qn heating with trimethyl phosphite or triethylamine, the major isomer furnishes the ( )-.yvn-2-alkene-l,4-diol by Mislow rearrangement1 lb. 

The spontaneous rearrangement of allyl p-toluenesulphenates to allyl sulphoxides was independently recorded by Mislow and coworkers and Braverman and Stabinsky. Mislow and colleagues201 have demonstrated that simple allyl alcohols such as 149, on conversion to the corresponding lithium alkoxides followed by treatment with arenesulphenyl chlorides, may be smoothly transformed at room temperature via the sulphenate esters into allylic sulphoxides 150 (equation 83). Braverman and Stabinsky202 have found that when the more reactive trichloromethanesulphenyl chloride is treated with allyl alcohol and pyridine in ether at — 70°, it affords trichloromethyl allyl sulphoxide and not allyl trichloromethanesulphenate as reported by Sosnovski203 (equation 84). 

The allyl sulphenate-allyl sulphoxide rearrangement is a general reaction and is applicable to structurally diverse allyl alcohols204,205 (Table 13). Mechanistically, it represents a typical example of a [2,3]-sigmatropic rearrangement as shown by the detailed investigations of Mislow and Braverman and their coworkers. 

Treatment of (—)-(S)-276 with allyl Grignard reagents gives optically active allylic sulphoxides 288. This reaction, however, involves an allylic rearrangement via transition state 289 as evidenced by Mislow and his collaborators362 (equation 160). 

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