Tamao

Reviews K. Tamao, in Comprehensive Organic Synthesis, Vol. 3, Pergamon Press, Oxford, 1991, p, 435 D. W. Knight, in Comprehensive Organic Synthesis, Vol. 3, Pergamon Press, Oxford. 1991, p, 481. 

Sh. Yamaguchi and K. Tamao, Yuki Gosei Kagaku Kyokaishi 56, 500 (1998). 

The cyclohexyloxy(dimethyl)silyl unit in 8 serves as a hydroxy surrogate and is converted into an alcohol via the Tamao oxidation after the allylboration reaction. The allylsilane products of asymmetric allylboration reactions of the dimethylphenylsilyl reagent 7 are readily converted into optically active 2-butene-l, 4-diols via epoxidation with dimethyl dioxirane followed by acid-catalyzed Peterson elimination of the intermediate epoxysilane. Although several chiral (Z)-y-alkoxyallylboron reagents were described in Section 1.3.3.3.3.1.4., relatively few applications in double asymmetric reactions with chiral aldehydes have been reported. One notable example involves the matched double asymmetric reaction of the diisopinocampheyl [(Z)-methoxy-2-propenyl]boron reagent with a chiral x/ -dialkoxyaldehyde87. 

The introduction of a (dialkylamino)dimethylsilyl or dimethylphenylsilyl group makes it possible to introduce a hydroxy group stereospecifically by Tamao oxidation78 80. This was successfully applied in the synthesis of /rrw.y-4-hydroxy-5-alkylfuranones81. 

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