Regio- and π-Facial Selective Cycloadditions Involving 2-Phenyl-4-dimethylamino-1-thia-3-azabuta-1,3-diene and Allenic Esters: An Efficient Route to Novel 6-Alkylidene-6H-2-phenyl-5-ethoxycarbonyl-1,3-thiazines

Autor: Ashish Kapur, Tilak Raj, Mohan Paul S. Ishar, Amritpal Kaur, Navdeep K. Girdhar
Rok vydání: 2004
Předmět:
Zdroj: Synthesis. 2004:775-778
ISSN: 1437-210X
0039-7881
DOI: 10.1055/s-2004-815995
Popis: 2-Phenyl-4-dimethylamino-1-thia-3-azabuta-1,3-diene (4) undergoes regio- and stereoselective [4+2] cycloadditions with allenic esters on refluxing in CH 2 Cl 2 -beuzeue and the initially formed cycloadducts 6 furnish, afterelimination of dimethylamine, novel (E/Z)-6-alkylidene-6H-2-phenyl-5-ethoxycarbonyl-1,3-thiazines 7 and 8 in high yields. In the case of reaction with ethyl 2-methylbuta-2,3-dienoate, the adduct 6e has been isolated in very high yields.
Databáze: OpenAIRE