Copper(I)-catalyzed cross-coupling reaction of alkynylsilanes with 1-chloroalkynes

Cross‐Coupling Reactions to sp Carbon Atoms

“…Hosomi has actually isolated many of the Cu-acetylides formed from alkynylsilanes and CuCl, and has subsequently applied these intermediates in the cross-coupling with acid chlorides [225]. The reaction is also applicable to the synthesis of 1,3-diynes from aryl(chloro)ethynes, which often fail under Cadiot-Chodkiewicz conditions [226]. Higher yields were achieved in the absence of Pd catalyst for this procedure.…”

Acetylenic Coupling: A Powerful Tool in Molecular Construction

“…Dichloromethane has been found to be another good solvent for both the oxidant and the polymer formed. [51] R SiMe 3 R R CuCl, DMF, O 2 R = Ph 100% R = C 6 H 13 80% 60 °C, 3-6 h Scheme 7. [43,49] An interesting procedure, reported by Mori, Hiyama, and co-workers, allows direct coupling of trimethylsilyl-protected alkynes without previous removal of the protecting groups.…”

“…This mild procedure provides a general alkynylation method for organocopper reagents and is of particular interest for the coupling of highly sensitive alkyne derivatives. [51] The cross-coupling was carried out using catalytic amounts of CuCl and an excess of the haloalkyne in DMF at 80 8C and gave the corresponding unsymmetrically substituted diynes, by silicon to copper exchange, in moderate to high yields ( Table 2). Cross-coupling of alkynyl(phenyl)iodonium tosylates with alkynylcopper reagents.…”

Cross‐Coupling Reactions to sp Carbon Atoms

“…The subsequent catalytic cycle is analogous to that of the Sonogashira reaction, and consequently, this reaction has been referred to as the sila-Sonogashira-Hagihara coupling. This tactic has been adopted for the construction of a wide range of internal acetylenes and could also be employed for the synthesis of 1,3-diynes from chloroalkynes, which often fail under the Cadiot-Chodkiewicz conditions [329]. Significantly higher yields were, however, achieved in the absence of a Pd catalyst for this procedure and hence sparked interest in Pd-free variants of the sila-Sonogashira-Hagihara reaction.…”