Rhodium-catalyzed 1,4-addition of terminal alkynes to vinyl ketones

Rhodium‐ and Palladium‐Catalyzed Asymmetric Conjugate Additions

“…Alkyne as a nucleophile for Rh-catalyzed conjugate addition has been studied minimally, with the earliest reports employing only MVK as the acceptor and having long reaction times [202,203]. The major hurdle with Rh-catalyzed alkynylation is that an primary alkyne (146) is generally more reactive than an enone towards Rh-alkynylides (147), and this results in the preferential formation of alkyne dimer 1.6 Rh-Catalyzed ECA of Alkynes 45 (149) rather than the conjugate addition product 148 (Scheme 1.57).…”

Catalyzed Reactions of Alkynes in Water

“…[86] Chisholm et al also reported such a reaction catalyzed by the Rh metal complex RhA C H T U N G T R E N N U N G (acac)(CO) 2 (acac = acetylacetonate) in the presence of tris(o-methoxyphenyl)phosphine in aqueous dioxane solutions. [87] The conjugated addition of sp C À H bonds to carbon-carbon triple bonds is an important way to synthesize conjugated enynes which are important building blocks and essential units in a variety of biologically active compounds. Recently Li et al reported a facile and simple method to generate conjugated enynes by using a combination of Cu/Pd together with PPh 3 , in water and under an air atmosphere [Eq.…”

1, 4-Addition of Terminal Alkynes to Conjugated Enones in Water Using Green Catalyst Bis[(l)prolinato-N,O]Zn—An Environmentally Benign Protocol

“…In each of these cases, acetylides must be generated by deprotonation, which requires stoichiometric quantities of at least one metal. Recently, several examples of the 1, 4-addition of alkynes have emerged that have been catalyzed by transition metals [15][16][17][18][19][20]. These methods take advantage of the facile C-H insertion chemistry of alkynes to generate the acetylide, which then adds to the enone.…”