Cyclopropyl Building Blocks in Organic Synthesis. Part 124. Access to Variously Substituted 5,6,7,8-Tetrahydro-3H-quinazolin-4-ones via Diels—Alder Adducts of Phenyl Vinyl Sulfone to Cyclobutene-Anellated Pyrimidinones.

Access to Variously Substituted 5,6,7,8-

Access to Variously Substituted 5,6,7,8-Tetrahydro-3H-quinazolin-4-ones via Diels–Alder Adducts of Phenyl Vinyl Sulfone to Cyclobutene-Annelated Pyrimidinones

✍ Suryakanta Dalai; Vladimir N. Belov; Shamil Nizamov; Karsten Rauch; Dirk Finsing 📂 Article 📅 2006 🏛 John Wiley and Sons 🌐 English ⚖ 246 KB

## 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 enlar