Hydroxylamine configurational isomers

Stereoselectivity in reductions of acyclic oximes depends on the configuration of C=N bond. ( )-Isomer of oxime 89 produced syn-hydroxylamine 90 in excellent stereoselectivity in reaction with phenyldimethylsilane-trifluroacetic acid while giving anti-product in the reaction with lithium aluminium hydride. Stereoselectivity in reductions of (Z)-isomers of 89 was substantially lower in both cases (equation 62) . It can be assumed that the rules of stereoselectivity established in diastereoselective reduction of ketones can be applied to reduction of oximes as well. 

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