Efficient synthesis of benzylphosphine oxides and E-stilbenes
摘要:
A series of substituted benzylphosphine oxides has been synthesised by reduction of the corresponding (alpha-chlorobenzyl)phosphine oxide, derived from the benzaldehyde and chlorodiphenylphosphine, with either sodium borohydride (DMSO, 60-70 degrees C, 12 h) or tributyltin hydride and AIBN (C6H6. 80 degrees C, 2 h). Reaction of the (alpha-lithiobenzyl)phosphine oxide with aldehydes gave exclusively E-alkenes.
[reaction: see text] We describe a new, straightforward, and easy-to-handle method for achieving an unprecedented trimethylsilyl halide-catalyzed Michaelis-Arbuzov-like rearrangement. This rearrangement occurs at temperatures from room temperature to 80 degrees C and does not require addition of any alkyl halide. The scope and limitations of this new reaction are explored, as well as its mechanism
Copper-catalyzed C–P cross-coupling of arylmethyl quaternary ammonium salts via C–N bond cleavage
作者:Nutao Li、Feng Chen、Guanghui Wang、Qingle Zeng
DOI:10.1007/s00706-019-02535-y
日期:2020.1
AbstractA ligand-free copper-catalyzed C–P cross-coupling reaction of arylmethyl quaternary ammonium salts and diarylphosphine oxides in air is developed. Arylmethyl quaternary ammonium salts with various functional groups and a variety of dialkyl- and diarylphosphine oxides afford C–P cross-coupling products with good yields. This protocol requires no inert atmosphere, no ligand, and simple operation
Photochemistry of Substituted Benzyldiphenylphosphine Oxides
作者:Ningning Zhao、Douglas C. Neckers
DOI:10.1021/jo991761r
日期:2000.4.1
Photochemical reactions (lambda irr = 254 nm) of substituted benzyldiphenylphosphine oxides 1a-e have been investigated in benzene and acetonitrile. alpha-Cleavage from the singlet excited state is proposed as the primary process, and products formed both before and after escape of the primary intermediates from the solvent cage result. Radicals 2 and 3 are observed by nanosecond flash photolysis following