Synthesis of α-hydroxy phosphonates
A low catalyst loading of a chiral tethered bis(8-quinolinolato) (TBOx) aluminum(III) complex effectively catalyzes the addition of phosphites to aldehydes and aldimines to give enantioenriched α-hydroxy and α-amino phosphonates in high yields and enantioselectivities.
J. P. Abell, H. Yamamoto, J. Am. Chem. Soc., 2008, 130, 10521-10523.
Organic alkali metal compounds serve as highly efficient precatalysts for the hydrophosphonylation reactions of aldehydes and unactivated ketones with dialkyl phosphite under mild conditions. Hydrophosphonylation reactions catalyzed by 0.1 mol % n-BuLi were completed within 5 min for a broad range of substrates and generated a series of α-hydroxy phosphonates in high yields.
C. Liu, Y. Zhang, Q. Qian, D. Yuan, Y. Yao, Org. Lett., 2014, 16, 6172-6175.
A low catalyst loading of [(Me3Si)2N]3Ln(μ-Cl)Li(THF)3 catalyzes the hydrophosphonylation of aromatic aldehydes to give α-hydroxy phosphonates in excellent yields at room temperature within 5 min. The presence of LiCl in the catalyst is crucial for the catalytic activity.
Q. Wu, J. Zhou, Z. Yao, F. Xu, Q. Shen, J. Org. Chem., 2010, 75, 7498-7501.
An organocatalytic, direct synthesis of α-hydroxy phosphonates via reaction of aldehydes and ketones with trimethylphosphite in the presence of catalytic amounts of pyridine 2,6-dicarboxylic acid in water is simple, cost-effective and environmentally benign.
F. Jahani, B. Zamenian, S. Khaksar, M. Taibakhsh, Synthesis, 2010, 3315-3318.
An efficient and simple synthesis of α-hydroxy phosphonates has been achieved via reaction of aldehydes with trimethylphosphite in the presence of Amberlyst-15 in water. The reaction is highly selective with excellent yields under mild conditions.
M. Tajbakhsh, A. Heydari, M. A. Khalilzadeh, M. M. Lakouraj, B. Zamenian, S. Khaksar, Synlett, 2007, 2347-2350.
A very convenient reaction of trialkyl phosphites with aldehydes or ketones in the presence of hydrogen chloride gives dialkyl 1-hydroxyalkylphosphonates in good yields via an Arbusov-like reaction of oxonium salts derived from aldehydes or ketones. This reaction is an alternative to the well-known Abramov reaction.
W. Goldeman, M. Soroka, Synthesis, 2006, 3019-3024.