abstract |
The invention herein is directed to a process for the preparation of ethyl 3S-amino-4-pentynoate which involves treating 3-(trimethylsilyl)-2-propynal with L-phenylglycinol in toluene to produce αS- 3-(trimethylsilyl)-2-propynylidene amino!benzenethanol; reacting αS- 3-(trimethylsilyl)-2-propynylidene!amino!benzenethanol with BrZnCH 2 CO 2 t-Bu in THF/NMP to produce 1,1-dimethylethyl 3S- (2-hydroxy-1S-phenylethyl)amino!-5-(trimethylsilyl)-4-pentynoate; reacting the 1,1-dimethylethyl 3S- (2-hydroxy-1S-phenylethyl)amino!-5-(trimethylsilyl)-4-pentynoate with sodium periodate to form 1,1-dimethylethyl 3S- (phenylmethylene)amino!-5-(trimethylsilyl)-4-pentynoate; hydrolyzing 1,1-dimethylethyl 3S- (phenylmethylene)amino!-5-(trimethylsilyl)-4-pentynoate to produce 1,1-dimethylethyl 3S-amino-5-(trimethylsilyl)-4-pentynoate; transesterifying 1,1-dimethyl 3S-amino-5-(trimethylsilyl)-4-pentynoate and desilylating to produce ethyl 3S-amino-4-pentynoate. |