A highly efficient base-, metal-, and oxidant-free catalytic O–H insertion reaction of diazoalkanes and phosphinic acids in the presence of B(C₆F₅)₃ has been developed. This powerful methodology provides a green approach towards the synthesis of a broad spectrum of α-phosphoryloxy carbonyl compounds with good to excellent yields (up to 99% yield). The protocol features the advantages of operational simplicity, high atom economy, practicality, easy scalability and environmental friendliness.