Expedient approach for the synthesis of novel indenothiophene derivatives
摘要:
Gewald reaction of 2-(2,3-dihydro-5,6-dimethoxy-1H-inden-1-ylidene)malononitrile, elemental sulfur, and a catalytic amount of triethylamine furnished the new synthon 2-aminoindenothiophene-3-carbonitrile. Its reaction with conc. H2SO4 furnished the expected 2-amino-3-carboxamide derivative instead of the corresponding carboxylic acid. The key intermediates 2-aminoindenothiophene-3-carbonitrile and -3-carboxamide were used for the synthesis of tetracyclic indenothienopyrimidine derivatives by cyclocondensation reaction with acid chlorides, amides, formic acid, or hydrazine hydrate. Neat reactions of the carbonitrile with cyclic and aliphatic ketones in the presence of anhydrous ZnCl2 furnished pentacyclic and tetracyclic indenothienopyridine derivatives, respectively, in good yields. All new compounds were characterized by spectroscopic and analytical data.
The Use of Pinner Type Reaction for the Synthesis of New Indeno[2,1-<i>c</i>]pyridine-4-carbonitrile Derivatives
作者:Prashant S. Nikam、Shivaraj P. Patil、Shrikant B. Kanawade、Sachin A. Gangurde、Meenakshi Rathi、Raghunath B. Toche
DOI:10.1002/jhet.1990
日期:2015.1
An efficient and convenient route was developed for the synthesis of new pyridinecarbonitrile derivatives by using the Pinner type of reaction. The 2‐((E)‐2‐((dimethylamino)methylene)‐1,2‐dihydro‐5,6‐dimethoxyinden‐3‐ylidene) malononitrile 2 was reacted in the presence of dry HCl gas to yield 3‐chloro‐6,7‐dimethoxy‐9H‐indeno[2,1‐c]pyridine‐4‐carbonitrile (3) in good yield. The SNAr reaction on compound
通过使用Pinner型反应,开发了一种有效且方便的途径来合成新的吡啶腈衍生物。2-((E)-2-(((二甲氨基)亚甲基)-1,2-二氢-5,6-二甲氧基茚-3-3-亚丙基)丙二腈2在干燥HCl气体存在下反应生成3-氯- 6,7-二甲氧基-9 H-茚并[2,1 - c ]吡啶-4-腈(3)的收率很高。在S Ñ上化合物的Ar反应3与各种亲核得到3-取代的pyridinecarbonitriles 4,5,6,7,8,9 中等至良好的产量。