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Über thermische, eine Amino‐ Claisen ‐Umlagerung einschliessende. Reaktionen von N‐Propargyl‐naphthylaminen
Author(s) -
Scheurer H.,
Zsindely J.,
Schmid H.
Publication year - 1973
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.19730560141
Subject(s) - chemistry , propargyl , claisen rearrangement , medicinal chemistry , ring (chemistry) , steric effects , stereochemistry , catalysis , organic chemistry
Abstract N‐Propargyl‐1‐naphthylamine ( 1 ), the corresponding N‐butinylcompound 5 and N‐propargyl‐2‐naphthylamine ( 2 ) ‐ unlike N‐propargyl‐anilines ‐ on heating to 250° are converted to a mixture of py‐tetrahydro‐benzoquinolines and benzoquinolines (scheme 1). The mechanism of these reactions which are induced by a [3 s , 3 s ] rearrangement of the propargyl group and include a [1,5 s ] H‐shift is depicted in scheme 4. N‐Methylation of 1 and 2 reduces for steric reasons the rate of the [1,5 s ] H‐shifts; therefore ring closure of the allenylnaphthylamine intermediates to indols 13 and 14 is favoured (schemes 2 and 5).