1-Alkynylphosphine Sulfides Research Articles

Carbozincation of Substituted 2-Alkynylamines, 1-Alkynylphosphines, 1-Alkynylphosphine Sulfides with Et2Zn in the Presence of Catalytic System of Ti(O-iPr)4 and EtMgBr

The EtMgBr and Ti(O-iPr)4-catalyzed ethylzincation of 1-alkynylphosphine sulfides with Et2Zn in diethyl ether followed by hydrolysis and deuterolysis affords corresponding β,β-disubstituted 1-alkenylphosphine sulfides with high yield. The EtMgBr and Ti(O-iPr)4-catalyzed reaction of 2-alkynylamines, 1-alkynylphosphines, and 1-alkenylphosphine sulfides with Et2Zn in various solvents was studied. It has been found that the reaction of 2-alkynylamines and 1-alkynylphosphines in methylene chloride, hexane, toluene, benzene, and anisole leads to the selective formation of 2-alkenylamines and 1-alkenylphosphine oxides after oxidation with H2O2.

Synthesis of 3-Arylbenzofuran-2-ylphosphines via Rhodium-Catalyzed Redox-Neutral C-H Activation and Their Applications in Palladium-Catalyzed Cross-Coupling of Aryl Chlorides.

A new class of aryl-heteroarylphosphines, 3-arylbenzofuran-2-ylphosphines, was synthesized by [Cp*Rh(III)]-catalyzed redox-neutral cyclization of N-phenoxyacetamides with 1-alkynylphosphine sulfides and oxides followed by reduction. This step-economic reaction proceeds in excellent regioselectivity with a broad substrate scope. The application of the resulting air-stable trivalent-phosphine containing dicyclohexylphosphino moiety in palladium-catalyzed Suzuki-Miyaura coupling and Buchwald-Hartwig amination of aryl chlorides is also described.

Rhodium(III)-Catalyzed C-H Activation and Annulation with 1-Alkynylphosphine Sulfides: A Mild and Regioselective Access for the Synthesis of Bulky Phosphine Ligands.

We reported herein rhodium(III)-catalyzed C-H activation and annulation reactions for the synthesis of bulky phosphine ligands by using 1-alkynylphosphine sulfides as key starting materials. In the presence of [Cp*RhCl2]2 (5 mol %) and CsOAc (2.0 equiv), various N-(pivaloyloxy)benzamides (3.0 equiv) could react smoothly with 1-alkynylphosphine sulfides at 40 °C in MeOH/CF3CH2OH cosolvent without external oxidant. Using [Cp(Ph)RhCl2]2 as catalyst, the reaction can be performed under less loading of benzamides (2.0 equiv) and milder reaction conditions (25 °C) with higher regioselectivity. In a sequential cyclization/desulfidation process, this new method provides a variety of bulky heteroarylphosphines with an isoquinolin-1(2H)-one motif.

Direct transformation of organosulfur compounds to organophosphorus compounds: rhodium-catalyzed synthesis of 1-alkynylphosphine sulfides and acylphosphine sulfides

A rhodium-catalyzed method for the synthesis of organophosphorus compounds directly from organosulfur compounds was developed. In the presence of RhH(PPh3)4 and depe, the reaction of 1-alkylthioalkynes with tetraethyldiphosphine disulfide gave 1-alkynylphosphine sulfides. The same complex catalyzed the reaction of thioesters giving acylphosphine sulfides.

Synthesis of 2-Indolylphosphines by Palladium-Catalyzed Annulation of 1-Alkynylphosphine Sulfides with 2-Iodoanilines

Palladium-catalyzed annulation of 1-alkynylphosphine sulfides with 2-iodoanilines followed by desulfidation affords 3-substituted 2-indolylphosphines. This annulation/desulfidation sequential protocol offers a conceptually new approach to bulky heteroarylphosphines.

Regio- and Stereoselective Hydroamidation of 1-Alkynylphosphine Sulfides Catalyzed by Cesium Base

Regio- and stereoselective hydroamidation of 1-alkynylphosphine sulfides proceeds in the presence of cesium carbonate to provide (E)-2-amino-1-thiophosphinyl-1-alkenes. Asymmetric hydrogenation of the adducts catalyzed by an iridium complex followed by desulfidation yields 2-amino-1-phosphinoalkanes, which offers a new approach to chiral N,P-ligands that will potentially serve as ligands in asymmetric reactions.

Synthesis of Bulky Phosphines by Rhodium-Catalyzed Formal [2 + 2 + 2] Cycloaddition Reactions of Tethered Diynes with 1-Alkynylphosphine Sulfides

The reaction of tethered diynes with 1-alkynylphosphine sulfides under rhodium catalysis provides the corresponding phosphine sulfides having a bulky aryl group. The following desulfidation yields bulky phosphines that will potentially serve as ligands in transition-metal-catalyzed reactions.