Synthesis of 3-Aminofurans

Investigation of the cyclization of O-alkylated cyanoenols (9)[R = Ar, CN, R = Ar, H or R R = (CH2)4] in the presence of sodium ethylate revealed (84LA1702) that acylmethyl substituents (R = Ar CO or COMe) 

Furo[3,2-fa]benzothiophenes (37) were synthesized in an analogous way (91JHC269) by smooth cyclization of the cyanomethyl ether 36 in the presence of K2C03/DMF. The starting 2-cyano-3-hydroxybenzothiophene 35 was obtained from methyl 2-thiohydroxybenzoate and chloroacetonitrile. Under Vilsmeier conditions (POCl3/DMF), the 2-cyano-3-cyanomethoxy- 

The synthesis of the tetracyclic pyrido[3,2- ]furo [3,2-6Jbenzo[l,4j-diazepinone (47) starting with 2-cyano-3-hydroxypyridine (42) and 3- 

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SCHEME 5.8 Thiazolium-mediated MCR for the synthesis of 3-aminofuran derivatives 13. C02Me -... 

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