Synthetic Entry into 1-Phosphono-3-azabicyclo[3.1.0]hexanes
摘要:
3-Azabicyclo[3.1.0]hex-2-en-1-yl phosphonates were prepared in a five-step reaction route from beta-ketophosphonates. The key steps in this sequence are an atom-transfer radical cyclization and an unforeseen lithium halogen exchange with n-BuLi. The cyclization reaction proceeds with excellent diastereoselectivity. The resulting cyclic imines were reduced, and 3-azabicyclo[3.1.0]hexan-1-yl phosphonates were obtained.
The Preparation of 1H-Pyrazole-5-propanoic and 1H-Pyrazole-5-butanoic Acids from Dilithiated C(α),N-Carboalkoxyhydrazones and Succinic or Glutaric Acid Anhydrides
作者:A. Cameron Church、Madlene U. Koller、Sheila A. O'Grady、Charles F. Beam
DOI:10.1080/00397919608004575
日期:1996.7
Abstract C(α),N-Carboalkoxyhydrazones were dilithiated with excess lithium diisopropylamide, condensed with succinic or glutaric acid anhydride, and cyclized to 1H-pyrazole-5-propanoic or 1H-pyrazole-5-butanoic acids.