Start Date

2019

Description

  • Indolizines are a versatile heterocyclic core that occurs frequently in pharmaceutical leads for a variety of indications, including: anti-bacterial1 and anti-tumor agents,2 and targets for the treatment of Alzheimer’s disease,3 asthma,4 erectile dysfunction,5 and inflammation related to respiratory or cardiovascular disease.
  • While evaluating the scope of a Au(I)-catalyzed rearrangement of 2- propargyloxypyridine 1, 7 substituted indolizine 4 was discovered as an unexpected by-product (Scheme 1). The structure of indolizine 4 was confirmed by NMR and Xray analysis. Investigations revealed that acetophenone, originally present as an impurity in the reaction, is a key reagent. The use of acetophenone as the solvent, in the presence of 1-phenylethanol (5 equiv), was determined to be optimal.

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Jan 1st, 12:00 AM

Synthesis of Trisubstituted Indolizines from 2-Propargyloxypyridines

  • Indolizines are a versatile heterocyclic core that occurs frequently in pharmaceutical leads for a variety of indications, including: anti-bacterial1 and anti-tumor agents,2 and targets for the treatment of Alzheimer’s disease,3 asthma,4 erectile dysfunction,5 and inflammation related to respiratory or cardiovascular disease.
  • While evaluating the scope of a Au(I)-catalyzed rearrangement of 2- propargyloxypyridine 1, 7 substituted indolizine 4 was discovered as an unexpected by-product (Scheme 1). The structure of indolizine 4 was confirmed by NMR and Xray analysis. Investigations revealed that acetophenone, originally present as an impurity in the reaction, is a key reagent. The use of acetophenone as the solvent, in the presence of 1-phenylethanol (5 equiv), was determined to be optimal.