✦ LIBER ✦
1,3-cycloadditions of aliphatic thione S-methylides to dimethyl 2,3-dicyanofumarate and 2,3-dicyanomaleate; a test case for steric course and mechanism
✍ Scribed by Grzegorz Mloston; Elke Langhals; Rolf Huisgen
- Publisher
- Elsevier Science
- Year
- 1989
- Tongue
- French
- Weight
- 295 KB
- Volume
- 30
- Category
- Article
- ISSN
- 0040-4039
No coin nor oath required. For personal study only.
✦ Synopsis
The 1,3-cycloadditions of thione S-methylides 2 and 9 to dimethyl 2,3_dicyanofumarate and 2,3_dicyanomaleate are nonstere5speciFi.c. A preceding cis,trans isomerization of the unsaturated dipolarophiles catalyzed by the thiadiazolines (precursors of the thione S-methylides) had to be suppressed in order to clarify the stereochemical leakage during the cycloaddition.