کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5226734 | 1383584 | 2009 | 7 صفحه PDF | دانلود رایگان |
Lithiation/substitution of 4-aryl-6-methyl-3,4-dihydropyrimidin-2(1H)-one ester derivatives with n-BuLi can be directed selectively at N-3 or C-6 positions, depending upon nature and equivalents of the base used and ‘hardness or softness’ of the metalated site/electrophile used. Biginelli dihydropyrimidinone substrate appended with enantiopure N-protected l-phenylalanine amino acid chloride, at N-3 position after resolution and deprotection yielded both enantiomers of 3,4-dihydropyrimidinones.
Expeditiously metalated Biginelli 3,4-dihydropyrimidine-2(1H)-one (DHPM) derivatives, substituted with chiral auxiliaries (CA) at N-3 site, selectively, furnish access to enantiomerically pure DHPMs. However, appending CA at C-6 methyl did not allow clean separation of diastereomers.Figure optionsDownload as PowerPoint slide
Journal: Tetrahedron - Volume 65, Issue 21, 23 May 2009, Pages 4106–4112