Journal of the American Chemical Society, Vol.125, No.11, 3268-3272, 2003
Twisted amide reduction under Wolff-Kishner conditions: Synthesis of a benzo-1-aza-adamantane derivative
A synthesis of 4,5-benzo-1-aza-tricyclo[4.3.1.1(3,8)]undecane (1), a benzo-1-aza-adamantane derivative, is described and features a previously unknown application of the Wolff-Kishner reduction of a nonresonance stabilized or "twisted" amide. An intermediate amino ester is converted to a severely "twisted amide", which, when exposed to hydrazine in alcohol, provides the corresponding "twisted" amino hydrazone. Wolff-Kishner conditions (KOH/ethylene glycol, 200 degreesC) provide the reduced target 1 without hydrolysis to amino acid derivatives. These operations are conveniently performed in a single flask in high yield.