LITHIATION OF 7-TETRAHYDROBENZO[B]THIO[B]THIOPHENE-2-CARBOXAMIDE AND SYNTHESIS OF A NEW [1]BENXOTHIENO[2,3-C]PYRANONE

Deprotonation at the 3-position of the title amide with -butyllithiun- N,N,N',N'-tetramethylethylenediamine was followed by quenching with el ectrophiles, when the quenching was performed with p-methoxybenzaldehy de a secondary alcohol was obtained which cyclised upon treatment with ethanolic sodium hydroxide to give a new [1]benzothieno[2,3-c]pyranon e.