Diisopropylethylamine → tert-butyl 1-((2R)-3-(benzyloxy)-1-(2-methyl-1-oxo-4-phenyl-2,8-diazaspiro[4.6]undecan-8-yl)-1-oxopropan-2-ylamino)-2-methyl-1-oxopropan-2-ylcarbamate

Participants

Reaction Steps

A diastereomeric mixture. of 2-methyl-4-phenyl-2,8-diazaspiro[4.6]undecan-1-one (200 mg; 0.774 mmol) in MeCN (2.58 ml) was treated with (R)-3-(benzyloxy)-2-(2-(tert-butoxy carbonylamino)-2-methyl propanamido) propanoic acid (Intermediate 3A) (295 mg; 0.774 mmol) followed by DIPEA (541 ul; 3.10 mmol). After stirring for 5 minutes, ®T3P (amide coupling agent 50% in DMF, 904 ul, 1.548 mmol) was added and the mixture was stirred at RT overnight. The resulting mixture was diluted with water and extracted with EtOAc. The combined organic extracts were dried (MgSO4) and concentrated in vacuo. Purification by chromatography on silica eluting with 50-100% EtOAc in iso-hexane afforded the title compound;

Provenance & Evidence