A regiodivergent nickel-catalyzed hydrocyanation of 1-aryl-4-silyl-1,3-diynes is reported. When appropriate bisphosphine and phosphine–phosphite ligands are applied, the same starting materials can be converted into two different enynyl nitriles with good yields and high regioselectivities. The DFT calculations unveiled that the structural features of different ligands bring divergent alkyne insertion
Highly efficient synthesis of unsymmetrical 1,3-diynes from organoalane reagents and alkynyl bromides mediated by a nickel catalyst
作者:Song Mo、Xue-Bei Shao、Gang Zhang、Qing-Han Li
DOI:10.1039/c7ra02758c
日期:——
Highlyefficient and simple cross-coupling reactions of alkynylbromides with organoalane reagents for the synthesis of unsymmetrical 1,3-diynes derivatives using Ni(OAc)2 (2–5 mol%)/(o-furyl)3P (4–10 mol%) as a catalyst are reported. Excellent yields (up to 94%) were obtained for a wide range of substrates at rt or 60 °C for 2–3 h in Et2O or toluene.
Cobalt-Catalyzed Regio- and Stereoselective Hydrosilylation of 1,3-Diynes To Access Silyl-Functionalized 1,3-Enynes
作者:Hui Leng Sang、Yongyi Hu、Shaozhong Ge
DOI:10.1021/acs.orglett.9b01836
日期:2019.7.5
A regio- and stereoselective hydrosilylation of 1,3-diynes has been developed relying on catalysts generated from bench-stable Co(acac)2 and dppp ligand. A variety of symmetrical and unsymmetrical 1,3-diynes undergo this transformation, yielding the corresponding silyl-functionalized 1,3-enynes in high yields with excellent regioselectivity. Gram-scale reactions and further transformations of the silyl-containing
An iron-based catalytic system was developed for the cross-coupling of 1-bromoalkynes with terminalalkynes to selectively generate unsymmetrical 1,3-butadiynes in water under air. It was found that a combination of 1-bromoalkynes derived from less acidicterminalalkynes with more acidic counterparts would greatly enhance yields and selectivity for unsymmetrical 1,3-butadiynes. The reaction was also
A highlyefficient one‐pot procedure for the preparation of 1‐chloroalkynes and 1‐chlorobutadiynes from terminal and trialkylsilyl‐protected precursors is reported. This convenient reaction, proceeding under mild conditions, utilizes N‐chlorosuccinimide as the chlorinating agent and tolerates a range of functional groups.