Organophosphine syntheses via activation of the phosphorus‐silicon bond of silylphosphines

Abstract

This paper describes the recent advances in the syntheses of organophosphines by forming several types of phosphorus-carbon bonds via activation of the phosphorus-silicon bond of silylphosphines. In this account, the activation methods are classified into three types: nucleophile-induced activations, reactions with Lewis acid-activated electrophiles, and transition metal catalyzed reactions. Nucleophile-induced activations of silylphosphines, especially by a fluoride, generated a reactive phosphide equivalent for selective formation of a P-C bond. Silylphosphines also reacted selectively with Lewis acid-activated electrophiles. The Lewis acid mediated/catalyzed additions and substitutions, to form sp3-carbon-phosphorus bonds including an asymmetric reaction, are described. Several important types of transition metal catalyzed reactions of silylphosphines are also mentioned in this account. Selective formation of a P-C bond is achieved through these activations to produce a variety of functional organophosphines including optically active ones.

Preparation of phosphines through C–P bond formation

“…Activated [224–225] or unactivated alkynes were investigated as substrates. Phosphines as well as silylphosphines [65–66 226–227] or phosphine–borane complexes can be used as phosphinating agents. The addition reaction has been initiated in several ways including base [228–233], radical (thermal radical [234] or AIBN radical [77–78 83,235–236]) or transition metal activation.…”

Highly efficient reduction of tertiary phosphine oxides and sulfides with amine-assisted aluminum hydrides under mild conditions

“…Currently reduction of phosphine oxides [13][14][15][16], versus substitution reactions of carbon nucleophiles with P-Cl derivatives or of carbon electrophiles with alkali metal phosphides [7][8][9], and phosphination of alkenes, alkynes, or aromatic halids [10][11][12], is the major method of synthesis of phosphines. Among many reducing agents silanes and aluminum hydrides remain the reagents of choice for reduction of phosphine oxides [17][18][19][20][21][22][23][24][25].…”

Erratum: Synthesis of functional phosphines with ortho‐substituted aryl groups: 2‐RC6H4PH2 and 2‐RC6H4P(SiMe3)2 (R = i‐Pr‐ or t‐Bu)

“…The crude product was purified by vacuum distillation 95 • C (0.01 mmHg) to afford 3 (15.5 g, 69%) as a colorless liquid. 31 (5). To a cooled (−78 • C) solution of LiAlH 4 (2.1 g, 56 mmol) in Et 2 O (300 mL), a solution of 3 (15.5 g, 70 mmol) in Et 2 O (15 mL) was added.…”

“…Combining a P-aryl substituent with P-H or P-SiMe 3 functional groups at phosphorus results in reactive phosphines that are important building blocks in organic, main group, and organometallic chemistry [4,5]. Several representative reactions are shown in Scheme 1 to illustrate the utility of phosphines with P-Si functionalities.…”