REACTIVITY OF TERTIARY ENAMINE OF CYCLIC AND ACYCLIC 3,4-DIOXOBUTANOIC ACID-DERIVATIVES

Enaminoester 1a and enaminofuranone 2 with iodomethane, 2-chloro-1,3-d ithiane and phenyldiazonium tetrafluoroborate afford the products resu lting from electrophilic attack on the C-alpha to the carbonyl group. However, acyl chlorides with 1a yield O-acylated products. The above r eactives and 1a give the corresponding products of enamino group hydro lysis. Enamines 1a and 1b react with dichlorocarbene, generated in pha se transfer conditions, to yield chlorofuranones 17a and 17b and dimet hoxyacetamides 18a and 18b. p-Nitrophenylazide affords 1,2,3-triazol 2 0 in good yield by reaction with enaminoester 2; but when reacts with 2 gives in small amount the azoderivative 21. it is noteworthy that in the above cycloaddition reactions, the open-chained enaminoester 1a i s much more reactive than the enaminofuranone 2.