Reaction of N-vinylic phosphazenes with alpha,beta-unsaturated aldehydes. Azatriene-mediated synthesis of dihydropyridines and pyridines derived from beta-amino acids.
Aza-Wittig reaction of N-vinylic phosphazenes (1,2 addition), derived from diphenylmethylphosphine or derived from trimethylphosphine with alpha,beta-unsaturated aldehydes, leads to the formation of 3-azatrienes through a [2 + 2]-cycloaddition-cycloreversion sequence. The presence of an alkyl substituent in position 3 of N-vinylic phosphazenes increases the steric interactions, and [4 + 2] periselectivity (1,4 addition) is observed. Reaction of azatrienes with alpha,beta-unsaturated aldehydes yields pyridines.
Palacios
Francisco
F
Departamento de Química Organica I. Facultad de Farmacia, Apartado 450, 01080 Vitoria, Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU), Spain. francisco.palacios@ehu.es
Herran
Esther
E
Alonso
Concepción
C
Rubiales
Gloria
G
Lecea
Begoña
B
Ayerbe
Mirari
M
Cossío
Fernando P
FP
D000447:Aldehydes / Q000737:chemistry*; D000596:Amino Acids / Q000737:chemistry*; D001372:Aza Compounds / Q000737:chemistry*; D003198:Computer Simulation; D003500:Cyclization; D004095:Dihydropyridines / Q000138:chemical synthesis* / Q000737:chemistry; D008958:Models, Molecular; D015394:Molecular Structure; D010753:Phosphoranes / Q000737:chemistry*; D011725:Pyridines / Q000138:chemical synthesis* / Q000737:chemistry; D055672:Static Electricity
D000447:Aldehydes; D000596:Amino Acids; D001372:Aza Compounds; D004095:Dihydropyridines; D010753:Phosphoranes; D011725:Pyridines