ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
[(1,3-Dioxolan-2-ylidene)methyl]phosphonates and -phosphinates as [simple] Synthons in Heterocyclic SynthesisThe readily available [(1,3-dioxolane-2-ylidene)methyl]phosphonates and -phosphinates 2a-f (Scheme 1) can be transformed with amines to aliphatic ketene N,O-and N,N-acetales (see Scheme 2, 2a → 3-7). Alkanediamines yield with 2a-f the imidazolidines 8a-f and the hexahydropyrimidines 9a-d (Scheme 3). the oxazolidine derivatives 10a-e and the thiazolidine 11 are accessible under special reaction conditions starting from 2a, b (Scheme 4). Hydrazines react with the CN-group-containing ketene O,O-acetals 2a-c to the pyrazoles 12a-g, whereof 12a, d, e can be cyclized to pyrazolo[1,5-a]pyrimidines 13a-d (Scheme 5). Amidines as starting materials transform 2a-c in an analogous way to the pyrimidine derivatives 14a-c (Scheme 6).
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19920750109