Reactions of Oxime Dianions: Stereospecificity in Alkylation
نویسندگان
چکیده
n carbon.L However, no information on the stereochemistry of the alkylated products was ever reported. We now wish to report total stereospecificity in the formation and alkylation of the a-carbon, oxygen-dianions of aliphatic ketoximes. Treatment of acetoxime 1 with two equivalents of n-BuLi in THF at O°C for 15 minutes resulted in the formation of exclusively the x dianion 2, which upon deuteration afforded cleanly compound 3.3 That the deuteration had occurred only on the s_yc methyl group was shown clearly by the NMR spectrum of 2 in benzene which exhibited a multiplet for the wmethyl group (6 1.70, 2H) and
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