ChemInform Abstract: Double Nitro‐Mannich Reaction Utilizing in situ Generated N‐Trimethylsilylaldimines: Novel Four‐Component One‐Pot Synthesis of Nitroimines.

Abstract

TANAKA*, S.; OGUMA, Y.; TANAKA, Y.; ECHIZEN, H.; MASU, H.; YAMAGUCHI, K.; KISHIKAWA, K.; KOHMOTO, S.; YAMAMOTO, M.; Tetrahedron 64 (2008) 7, 1388-1396; Dep. Appl. Chem. Biotechnol., Fac. Eng., Chiba Univ., Inage, Chiba 263, Japan; Eng.) -Bartels 35-054

Synthesis of 6-Substituted 6-Nitroperhydro-1,4-diazepines via Novel Tandem Retro-Henry and Mannich/Michael Reactions

“…The retro-Henry reaction is well-known although rarely employed in organic synthesis; it normally involves a base-mediated process to obtain, in first instance, a carbonyl compound and a stabilized carbanion. This reaction can be applied to β-nitro alcohols and, as shown by Harada et al, to 6-hydroxymethyl-6-nitroperhydrodiazepines in order to replace the hydroxymethyl group with a hydrogen atom. The stable carbanion/nitronate 2 (Scheme ) was formed in a few minutes by reaction of 1 with a slight excess of t -BuOK in THF.…”