Copper(II)-catalyzed amidations of alkynyl bromides as a general synthesis of ynamides and Z-enamides. An intramolecular amidation for the synthesis of macrocyclic ynamides.

A general and efficient method for the coupling of a wide range of amides with alkynyl bromides is described here. This novel amidation reaction involves a catalytic protocol using copper(II) sulfate-pentahydrate and 1,10-phenanthroline to direct the sp-C-N bond formation, leading to a structurally diverse array of ynamides including macrocyclic ynamides via an intramolecular amidation. Given the surging interest in ynamide chemistry, this atom economical synthesis of ynamides should invoke further attention from the synthetic organic community.

A ring-closing yne-carbonyl metathesis of ynamides.

[reaction: see text] An acid-catalyzed ring-closing ynamide-carbonyl metathesis is described here. This hetero RCM methodology is applicable to the construction of carbocycles as well as heterocycles such as chromenes, quinolizidines, indolizidines, and pyrrolizidines.

Copper sulfate-pentahydrate-1,10-phenanthroline catalyzed amidations of alkynyl bromides. Synthesis of heteroaromatic amine substituted ynamides.

A practical cross-coupling of amides with alkynyl bromides using catalytic CuSO(4).5H(2)O and 1,10-phenanthroline is described here. This catalytic protocol is more environmentally friendly than the use of CuCN or copper halides and provides a general entry for syntheses of ynamides including various new sulfonyl and heteroaromatic amine substituted ynamides. Given the interest in ynamides, this N-alkynylation of amides should be significant for the future of ynamides in organic synthesis.

Highly stereoselective synthesis of novel alpha-haloenamides via a mild and efficient hydrohalogenation of ynamides.

A highly stereoselective preparation of novel chiral (E)-alpha-haloenamides under mild conditions utilizing magnesium halide salts is described. This unexpected mild and efficient hydrohalogenation reaction highlights another synthetic utility of ynamides. [reaction: see text]

A copper-catalyzed C-N bond formation involving sp-hybridized carbons. A direct entry to chiral ynamides via N-alkynylation of amides.

A copper-catalyzed new C-N bond formation involving a sp-hybridized carbon is described here leading to a facile entry for syntheses of chiral ynamides. This direct N-alkynylation of amides should have a significant impact on the future development of synthetic methodologies employing ynamides.