Lithiierung in α‐Stellung zum N‐Atom von Triphenylacetamiden aus cyclischen sekundären Aminen. Umlagerung metallierter Triphenylacetamide unter 1,3‐Verschiebung der Carbamoylgruppe

Lithiation in α‐Position to the N‐Atom of Triphenylacetamides from Cyclic Secondary Amines. Rearrangements of Metalated Triphenylacetamides by 1,3‐Shift of Carbamoyl Groups The reagents 2 ‐ generally available by lithiation of the triphenylacetamides 1 ‐ react with non‐enolizable carbonyl compounds and benzyl halide (s. Tables 1 and 2 , and products 3 ). The limits of thermal stability of metalated triphenylacetamides above 0° are caused by a 1,3‐shift of the carbamoyl group into the o ‐position of one of the benzene rings (s. 2b → 4 and 8a → 10 ). The barriers to rotation around the amide bonds of four triphenylacetamides are ca. 16 kcal/mol (s. 1b–e in Table 1 ).