tert-Butoxy bis(dimethylamino)methane → Di-tert-butyl (1S,2R,5R,6R)-2-(tert-butoxycarbonylamino)-3-(dimethylaminomethylene)-4-oxo-bicyclo[3.1.0]hexane-2,6-dicarboxylate

Participants

Reaction Conditions

Reaction Steps

Tert-butoxybis(dimethylamino)methane (481.1 ml, 2.33 mol) is added to a suspension of di-tert-butyl(1S,2S,5R,6R)-2-[(tert-butoxycarbonyl)amino]-4-oxobicyclo[3.1.0]hexane-2,6-dicarboxylate (600 g, 1.46 mol) in dry toluene (3.6 L) at room temperature under nitrogen. The mixture is heated at 80° C. for 3 hour and 45 minutes, then cooled to room temperature and stirred overnight. The reaction volume is reduced in vacuo, diluted with methyl tert-butyl ether (1.8 L) and hexane (1.8 L), and stirred for 3 hours at 15° C. After 3 hours, the resulting solid is collected by filtration, washed with cold hexane (2×1.8 L), and dried under vacuum to obtain the title compound (620.4 g, yield 91%). HPLC-MS: 98%.

Provenance & Evidence