A Convenient Synthesis of (S)-2-Methyl and (2S)-2,3-Dimethyl Butyl Phenylsulfones from (S)-(-)-3-Methyl-γ-butyrolactone

References

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• The sulfone (4a) could also be prepared from the sulfone-alcohol (4b) prepared from alcohol (3a) in 75% yield (m-CPBA in dichloromethane, 18 h at room temperature). Alcohol (4b) was mesylated (82%) and (4c) selectively reduced to (4a) with LiAIH4 (refluxing diethyl ether, 3 h, 55% yield of isolated product). Optical purity of final product (4a) was practically identical to that exhibited by the same product prepared from the phenylsulfide (3d) [α]D = +13.1, c 3.5 in CHCl3
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