Premium
A Facile Synthesis of Substituted 1,4‐Benzothiazepin‐5(4 H )‐ones and Pyrido[3,2‐ f ][1,4]thiazepin‐5(4 H )‐ones − Crystal and Molecular Structure of 2‐Ethylthio‐4‐methyl‐5(4 H )‐oxopyrido[3,2‐ f ][1,4]thiazepine‐3‐carbonitrile
Author(s) -
Dölling Wolfgang,
Biedermann Matthias,
Hartung Helmut
Publication year - 1998
Publication title -
european journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 1434-193X
DOI - 10.1002/(sici)1099-0690(199806)1998:6<1237::aid-ejoc1237>3.0.co;2-2
Subject(s) - chemistry , ring (chemistry) , intramolecular force , ketene , nucleophilic substitution , derivative (finance) , nucleophile , carbon disulfide , crystal structure , alkylation , medicinal chemistry , stereochemistry , crystallography , organic chemistry , catalysis , financial economics , economics
A new synthesis of pyrido[3,2‐ f ][1,4]thiazepine derivatives 3 starting with 2‐chloronicotinic acid ( 1 ), methylaminoacetonitrile hydrochloride and carbon disulfide is described. As proved by a crystal structure determination, a boat conformation with approximated mirror symmetry can be assigned to the 1,4‐thiazepine ring in 3b . 2‐Chloro‐ N ‐cyanomethyl‐ N ‐methyl‐5‐nitrobenzamide ( 5 ) reacts with carbon disulfide in presence of a strong base in DMF or DMSO depending on the temperature to either the benzothiopyran compound 6 or by intramolecular aromatic nucleophilic substitution to a seven‐membered ring system as thiolate anion which can be alkylated to give the 1,4‐benzothiazepine derivative 7 , or to an open‐chain amido ketene dithioacetal 8 .