反应详情

Following the procedure for the preparation of dicyclopropyl(1-hydroxy-1-methylethyl)methylsilane (see Example 1), dicyclopropyl(ethyl)(1-hydroxy-1-methylethyl)silane was prepared from the precursors chloro(dicyclopropyl)ethylsilane and acetyl(dicyclopropyl)ethylsilane. Reaction of trichloro(ethyl)silane (10.2 g, 62.4 mmol) with cyclopropyl lithium (prepared from bromocyclopropane (15.2 g, 126 mmol) and Li (1.80 g, 259 mmol) in Et2O (80 ml)) followed by distillation (79° C., 20 mbar) afforded 5.43 g (50%) of dicyclopropyl(ethyl)chlorosilane. Reaction of dicyclopropyl(ethyl)chlorosilane (5.00 g, 28.6 mmol) with ethoxyvinyl lithium (prepared from ethyl vinyl ether (2.52 g, 35.0 mmol) and tert-butyl lithium (1.9 M in pentane, 16.5 ml, 31.4 mmol) in THF (45 ml)) followed by hydrolysis with acetone/1 N HCl (2:1, 64 ml) and purification by silica-gel chromatography (silica gel 40-63 μm, hexane/EtOAc, 9:1) afforded 2.00 g (38% over 2 steps) of acetyl(dicyclopropyl)ethylsilane, of which 1.10 g (6.03 mmol) was reacted with methyl lithium (1.6 M in Et2O, 33.9 ml, 54.2 mmol) to provide after purification by silica-gel flash chromatography (silica gel 15-40 μm, hexane/EtOAc, 9:1) 720 mg (60%) of the odoriferous title compound.

1. distillationfollowed by distillation (79° C., 20 mbar)