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Zur Reaktionsweise von Enaminen mit Cyclopropenonen II
Author(s) -
Bilinski V.,
Steinfels M. A.,
Dreiding A. S.
Publication year - 1972
Publication title -
helvetica chimica acta
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.74
H-Index - 82
eISSN - 1522-2675
pISSN - 0018-019X
DOI - 10.1002/hlca.19720550404
Subject(s) - chemistry , enamine , ring (chemistry) , stereochemistry , medicinal chemistry , computational chemistry , organic chemistry , catalysis
The addition of diphenylcyclopropenone 2 to several enamines 1 as described by Ciabattoni & Berchtold [1] [2] has been reinvestigated. The products which were previously postulated to be enamines of β‐dicarbonylcompounds 9 to 14 have now been shown to be ‘amides’ 16 to 20 . The reaction does not take the course of a ‘C, C‐insertion’, which would have been useful for ring expansion, but rather of a ‘C, N‐insertion’, which attaches a C 3 side chain to the α‐carbon of enamines. This conclusion was reached by new interpretations of spectral data and by chemical transformations of old and new products. In the course of this reinvestigation, a new class of products, the amino‐cyclopentenones 41 , 45 and 47 , were isolated from the enamine‐cyclopro‐penone‐reaction. Their structures were proven by spectroscopic considerations and by chemical degradation. A systematic representation of these reactions is proposed in the reaction scheme.