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We report one-pot and chemoselective Knoevenagel-type reactions using highly stable amides and lactams as the electrophilic substrates. The method is based on the in situ activation of amide carbonyl with triflic anhydride and a subsequent reaction with carbanions generated in situ from carbonyl compounds. The amide-based method is an alternative to the versatile thioamide-based Eschenmoser sulfide contraction.

A 10-step asymmetric synthesis of 9-epi-sessilifoliamide J (20), together with sessilifoliamide J (6), has been accomplished from the key chiral building block 11 via a threo-selective vinylogous Mannich reaction and a Ley oxidation-SmI(2)-mediated coupling lactonization. The absolute configuration of the natural sessilifoliamide J was established.

We report the first one-pot reductive homocoupling reaction of secondary amides and cross-coupling reaction of secondary amides with ketones to give secondary vicinal diamines and amino alcohols. This method relies on the direct generation of α-amino carbon radicals from secondary amides by activation with trifluoromethanesulfonic anhydride, partial reduction with triethylsilane and samarium diiodide-mediated single-electron transfer. The reactions were run under mild conditions and tolerated several functional groups.