Access to Variously Substituted 5, 6, 7, 8??Tetrahydro??3H??quinazolin??4??ones via Diels–Alder Adducts of Phenyl Vinyl Sulfone to Cyclobutene??Annelated …
S Dalai, VN Belov, S Nizamov, K Rauch…
文献索引：Dalai, Suryakanta; Belov, Vladimir N.; Nizamov, Shamil; Rauch, Karsten; Finsinger, Dirk; De Meijere, Armin European Journal of Organic Chemistry, 2006 , # 12 p. 2753 - 2765
Abstract Under basic conditions (Et 3 N, dioxane), the aromatic amidines 4 and also S- methylisothiourea 4g cleanly undergo Michael addition to methyl 2-chloro-2- cyclopropylideneacetate (5), followed by intramolecular nucleophilic substitution, cyclopropyl to cyclobutyl ring enlargement, deprotonation and cyclization with elimination of methanol to afford the cyclobutene-annelated pyrimidinones 6 in 43–83% yield (7 ...
