کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5218369 | 1383325 | 2013 | 6 صفحه PDF | دانلود رایگان |
All four stereoisomers of 2-(aminomethyl)cyclobutane-1-carboxylic acid have been prepared starting from a single chirally derivatized unsaturated γ-lactam. A photochemical [2+2] cycloaddition reaction of this compound with ethylene was employed to create the four-membered ring exclusively with a cis ring configuration. The two diastereoisomers were separated conveniently by chromatography then the chiral appendage replaced by the more convenient Boc protecting group. Base-mediated lactam hydrolysis provided each of the cis target structures as single enantiomers. An efficient, tandem epimerization/hydrolysis protocol was applied to a carboxamide derivative of each cis compound, to furnish the corresponding trans compounds as single isomers, for the first time.
Figure optionsDownload as PowerPoint slide
Journal: Tetrahedron - Volume 69, Issue 17, 29 April 2013, Pages 3571–3576