Thiophenecarboxylic acids, amino-, reaction

Reaction between 3-amino-2-thiophenecarboxylic acid and R2GeCl2 with a deficiency of the L1NH2 gives the monoamino compounds 158 while an excess of lithium amide leads to formation of the diamino derivatives 159513 515-516 p(le authors suggest that intermolecular O — Ge coordination increases the lability of chlorine substituent in the intermediate 158 and favors the formation of the diamino derivatives 159510 513-515... 

A numerous series of compounds containing a N,O-chelating ligand, namely the derivatives of anthranilic (157) and 3-amino-2-thiophenecarboxylic (158 and 159) acids, were prepared by the reactions of organohalogermanes with esters, amides or lithium derivatives of acids510-516. 

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