Synthesis of new substituted 7,12-dihydro-6,12-methanodibenzoc,fazocine-5-carboxylic acids containing a tetracyclic tetrahydroisoquinoline core structure

• Published in: Beilstein journal of organic chemistry Vol. 17; p. 2511
• Main Authors: Grajewska, Agnieszka, Chrzanowska, Maria, Adamska, Wiktoria
• Format: Journal Article
• Language: English
• Published: 01.01.2021
• ISSN: 1860-5397; 1860-5397
• DOI: 10.3762/bjoc.17.168

A convenient and simple protocol has been developed for the synthesis of a series of new tetracyclic tetrahydroisoquinoline derivatives, 7,12-dihydro-6,12-methanodibenzo[c,f]-azocine-5-carboxylic acids by three component Petasis reaction with the use of aminoacetaldehyde acetals bearing substituted benzyl groups as the amine components followed by Pomeranz-Fritsch double cyclization reaction. By applying this method, several acids have been prepared in satisfactory yields. An unprecedented chemical behavior of a Petasis reaction product in diluted HCl solution leading to the formation of a phenylglycine derivative has been observed and the mechanism explaining such reactivity has been proposed.A convenient and simple protocol has been developed for the synthesis of a series of new tetracyclic tetrahydroisoquinoline derivatives, 7,12-dihydro-6,12-methanodibenzo[c,f]-azocine-5-carboxylic acids by three component Petasis reaction with the use of aminoacetaldehyde acetals bearing substituted benzyl groups as the amine components followed by Pomeranz-Fritsch double cyclization reaction. By applying this method, several acids have been prepared in satisfactory yields. An unprecedented chemical behavior of a Petasis reaction product in diluted HCl solution leading to the formation of a phenylglycine derivative has been observed and the mechanism explaining such reactivity has been proposed.