α-Diazocarbonyl compounds and enamines - a dichotomy of reaction paths

✍ Scribed by Rolf Huisgen; Hans-Ulrich Reissig; Helmut Huber; Sabine Voss

• Book ID: 104212638
• Publisher: Elsevier Science
• Year: 1979
• Tongue: French
• Weight: 246 KB
• Volume: 20
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)70991-9

✦ Synopsis

2,5-Dimethyl-l -pyrroIidinocyclopentene produces with methyl diazoacetate and diazoketones Summary 2-pyrazolines OS cycloadducts whereas with dimethyl diazomalonote an CIZO coupling equilibrium is established. The rate constants of these two reactions respond differently to solvent polarity. N-Cyclohexenyldialkylamines 1, n = 6, and enomines derived from open-chain carbonyl compounds undergo 1,3dipolar cycloadditions with diazoacetic ester 1,2 or diazomalonic ester 2 to give 1 -pyruzolines 2 which subsequently may tautomerize to P-pyrazolines and eliminate HNR2 to yield pymzoles 3. I,2