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An intramolecular C-N cross-coupling of ?-enaminones: a simple and efficient way to precursors of some alkaloids of Galipea officinalis.

ABSTRACT: 2-Aroylmethylidene-1,2,3,4-tetrahydroquinolines with the appropriate substituents can be suitable precursors for the synthesis of alkaloids from Galipea officinalis (cuspareine, galipeine, galipinine, angustureine). However, only two, rather low-yielding procedures for their synthesis are described in the literature. We have developed a simple and efficient protocol for an intramolecular, palladium or copper-catalysed amination of both chloro- and bromo-substituted 3-amino-1,5-diphenylpent-2-en-1-ones leading to the above-mentioned tetrahydroquinoline moiety. The methodology is superior to the methods published to date.

SUBMITTER: Dousova H

PROVIDER: S-EPMC4464440 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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An intramolecular C-N cross-coupling of β-enaminones: a simple and efficient way to precursors of some alkaloids of Galipea officinalis.

Doušová Hana H Horák Radim R Růžičková Zdeňka Z Šimůnek Petr P

Beilstein journal of organic chemistry 20150527

2-Aroylmethylidene-1,2,3,4-tetrahydroquinolines with the appropriate substituents can be suitable precursors for the synthesis of alkaloids from Galipea officinalis (cuspareine, galipeine, galipinine, angustureine). However, only two, rather low-yielding procedures for their synthesis are described in the literature. We have developed a simple and efficient protocol for an intramolecular, palladium or copper-catalysed amination of both chloro- and bromo-substituted 3-amino-1,5-diphenylpent-2-en- ...[more]

PMID: 26124890

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