Brønsted Acid-Mediated Annulation of α-Oxo Ketene Dithioacetals with Pyrroles: Efficient Synthesis of Structurally Diverse Cyclopenta[<i>b</i>]pyrroles
Brønstedacid‐mediated annulation of internal olefins α‐oxo ketene dithioacetals to pyrroles was efficiently achieved to afford cyclopenta[b]pyrroles. A pair of Brønstedacids with acid strengths, that is, trifluoroacetic acid, and para‐toluenesulfonic acid hydrate, were applied to promote the annulation reactions. The resultant products were readily oxidized to sulfones by meta‐chloroperoxybenzoic
Regioselective synthesis of substituted 1-methyl- and 2-methylnaphthalenes
作者:K Mallik Yadav、Pramod K Mohanta、Hiriyakkanavar Ila、Hiriyakkanavar Junjappa
DOI:10.1016/0040-4020(96)80832-5
日期:1996.10
Regiospecificallysubstituted 1-methyl- and 2-methylnaphthalenes, 5-methyl- and 6-methyl-1,2,3,4-tetrahydroanthracenes have been synthesized in good yields through 1,2- addition of the corresponding α-lithio-o-or m-xylenes onto α-oxoketenedithioacetals or their dihydro derivatives followed by cyclodehydration of the resulting carbinols in the presence of borontrifluoride etherate.