Studies on the Efficient Generation of PhosphorusCarbon Bonds via a Rearrangement of P^III Esters Catalysed by Trimethylhalosilanes

Abstract

Halotrimethylsilanes Me(3)SiX (X = Br, I) catalyse rearrangements of tricoordinate phosphorus esters R'R''P-OR into the corresponding phosphoryl systems R'R''P(O)R. This provides a simple and efficient route to a variety of structures containing phosphorus-carbon bonds, under mild conditions and with good yields. The reaction mechanism was investigated in detail by (31)P NMR spectroscopy and independent synthesis of the reaction intermediates. It has been demonstrated that the primary products of this catalytic reaction are halogeno P(III) structures R'R''PX and silyl ethers ROSiMe(3) and that they subsequently react to give the corresponding phosphorus silyl esters-Me(3)SiOPR'R''-and alkyl halides RX. At higher temperatures these intermediates then react to form R'R''P(O)R compounds. This paper also features the surprising observation that when esters Ph(2)POR and halotrimethylsilanes Me(3)SiX (X = Br, I) are used in 2:1 ratio, phosphonium salts Ph(2)R(2)P(+)X(-) and trimethylsilyl diphenylphosphinate--Ph(2)P(O)OSiMe(3)--are formed as the major products. Experimental evidence indicates that the mechanisms of both reactions are fundamentally different from that of the Michaelis-Arbuzov reaction. Me(3)SiCl is not reactive and this paper explains why.

A derivatization strategy for the detection and identification of volatile trialkylphosphites using liquid chromatography-online solid phase extraction and offline nuclear magnetic resonance spectroscopy

“…Among several reactions attempted, facile and clean Michaelis Arbuzov reaction [30][31][32] was found to take place under soft reaction conditions, using cheap and easily available starting materials. This reaction (as shown in Fig.…”

Improvements, Variations and Biomedical Applications of the Michaelis–Arbuzov Reaction

“…Trimethylsilyl halides Me 3 SiX (TMSX, where X = Br, I) catalyze the rearrangement of phosphites, but also phosphinites and phosphinates to phosphonates, as shown in Scheme 20 . The trimethylsilyl chlorides do not react [ 32 , 33 ]. The mechanism of the reaction is illustrated in Scheme 21 along with two representative examples.…”

“…The first example in Scheme 21 demonstrates the conversion of a borneol phenylphosphonate to a phosphinic derivative. Other examples with modification of natural products have been described [ 32 ].…”

Catalytic Deoxygenative Coupling of Aromatic Esters with Organophosphorus Compounds

“…Diphenyl(thiophen-2-ylmethyl)phosphine oxide (3A) [18] Purification by PTLC (hexane/acetone = 1:3) afforded 3A as a white solid (53.1 mg, 89% yield). 1 (Furan-2-ylmethyl)diphenylphosphine oxide (3C) [19] The reaction was conducted by using 3.0 equiv of 2A. Purification by PTLC (hexane/acetone = 1:1) afforded 3C as a yellow solid (51.3 mg, 91% yield).…”