672-66-2Relevant articles and documents
Reduction of tertiary phosphine oxides to phosphine-boranes using Ti(Oi-Pr)4/BH3-THF
Sowa, Sylwia,Pietrusiewicz, K. Micha?
supporting information, (2021/03/17)
A new method for reduction of tertiary phosphine oxides leading to the formation of tertiary phosphine-boranes has been developed. The BH3-THF/Ti(Oi-Pr)4 reducing system enables conversion of triaryl, diarylalkyl and trialkylphosphine oxides directly to their borane analogues in good to high yields. In contrast to the previously reported protocols, the presence of activating groups in the structure of starting material is not necessary for the reaction to occur. The reaction is highly stereoselective and proceeds with predominant retention of configuration at the phosphorus atom. A plausible mechanism of reduction of the P[dbnd]O bond by BH3-THF/Ti(Oi-Pr)4 has been proposed.
Synthesis of Molybdenum(VI) Neopentylidene Neopentylidyne Complexes
Tafazolian, Hosein,Schrock, Richard R.,Müller, Peter
supporting information, p. 2888 - 2891 (2019/08/30)
Mo(C-t-Bu)(CH-t-Bu)(Cl)(PMe2Ph)2 (1) was prepared as off-white crystals in 26% yield through addition of 2.5 equiv of Mg(CH2-t-Bu)2 to Mo(O)[OC(CF3)3]4 in diethyl ether followed by 3 equiv of PMe2Ph and a workup that includes dichloromethane (the source of Cl). Compound 1 is largely a syn isomer initially that equilibrates to give approximately a 1:1 mixture of syn and anti isomers within 1-2 h. Compound 1 reacts with Li(3,5-dimethylpyrrolide) to give Mo(C-t-Bu)(CH-t-Bu)(η1-Me2Pyr)(PMe2Ph)2 (2a) as a pale yellow solid in 76% yield, and 2a reacts with Ph3SiOH to give a mixture of syn and anti Mo(C-t-Bu)(CH-t-Bu)(OSiPh3)(PMe2Ph)2 (3a) in 84% yield. All three compounds tend to lose PMe2Ph to give 14e monophosphine complexes with the formulas Mo(C-t-Bu)(CH-t-Bu)(X)(PMe2Ph) (X = Cl, Me2Pyr, or OSiPh3), none of which could be isolated. X-ray studies show the structures of 1, 2a, and 3a to be analogous with τ values of 0.45, 0.53, and 0.69, respectively.
A study on the deoxygenation of trialkyl-, dialkyl-phenyl- and alkyl-diphenyl phosphine oxides by hydrosilanes
Kovács, Tamara,Urbanics, Anita,Csatlós, Flóra,Keglevich, Gy?rgy
, (2017/08/26)
The deoxygenation of 1-alkyl-3-methyl-3-phospholene 1-oxides, which may be regarded as trialkyl phosphine oxides (R3PO), and the reduction of dialkyl-phenylphosphine oxides (R2PhPO) and methyl-diphenylphosphine oxide (MePh2PO) have been elaborated by applying user-friendly silanes, such as tetramethyldisiloxane (>SiH–O–HSin) under solvent-free, catalyst-free, and microwave (MW)-assisted conditions. New silanes of type Ar2SiH2, alkyl2SiH2, and Ar3SiH were also applied in a few cases. The reactivity of the phosphine oxides and the silanes could be mapped on the basis of our experimental data.