Copper-Catalyzed Oxidative sp³-Carbon Radical Cross-Coupling with Trialkylphosphites Leading to α-Phosphonyl 1,3-Dicarbonyl Compounds

Abstract

A copper-catalyzed radical Csp3 –H/P­(OR)3 cross-coupling reaction for the formation of Csp3 –P bonds is described. A range of 1,3-dicarbonyl compounds and trialkylphosphites were coupled in this fashion to give the corresponding products in moderate to good yields. This protocol provides direct access to α-phosphonyl 1,3-dicarbonyl compounds.

Recent Advances in C(sp3)—H Phosphorylation Based on Secondary Phosphine Oxides and Phosphite Esters

“…The copper-catalyzed radical approach was also utilized in α-C(sp 3 )-H phosphorylation of 1,3-dicarbonyl compounds. Recently, the group of Bao and Zou [66] developed a copper-catalyzed radical cross-coupling reaction of α-C(sp 3 )-H bond of 1,3-dicarbonyl compounds and trialkyl phosphites using CuBr (10 mol%) and lauroyl peroxide (LPO) in HOAc at 110 ℃ (Scheme 15). This protocol provides a direct synthetic method of α-phosphonyl 1,3-dicarbonyl compounds.…”

Iron-catalyzed C(sp3)–H phosphorylation via photoinduced LMCT

“…These observations provide additional evidence supporting the feasibility of the direct radical addition to chlorophosphorus. 13 Furthermore, density functional theory (DFT) computational studies on the radical phosphination step were conducted and comparable results were obtained (Scheme 2C). With chlorodiphenylphosphine as an phosphination partner, the computational analysis of the phosphination step shows an activation free energy of 8.6 kcal mol −1 , which is significantly lower than the activation free energy of 13.5 kcal mol −1 when using diphosphines.…”

Metal-Free Phosphination and Continued Functionalization of Pyridine: A Theoretical Study

“…In light of their fundamental importance, many methods of C-P bond formation have been developed [ 4 , 5 , 6 ]. Among these methods, transition-metal-catalyzed cross-coupling reactions, including the Pd- [ 7 ], Cu- [ 8 ], Zn- [ 9 ], Ni- [ 10 ], Mn- [ 11 ], Ag- [ 12 ], and Rh-catalyzed [ 13 ] phosphination reactions of various aryl partners with phosphine reagents, have received great attention [ 14 ]. In particular, researchers have focused on developing a mild, efficient, and environmentally benign method of C–P bond formation [ 15 , 16 , 17 ].…”