AbstractA series of dibenzyl α‐hydroxyphosphonates and the corresponding α‐hydroxyphosphonic acids, mostly new compounds, have been synthesized. The dibenzyl α‐hydroxyphosphonates have been obtained in the Pudovik reaction of substituted benzaldehydes and dibenzyl phosphite in the presence of triethylamine as the catalyst. The amount of the solvent was minimized during the reaction, and the workup involved crystallization from the reaction mixture. A new protocol was developed to transform the dibenzyl 1‐hydroxyphosphonates to the corresponding phosphonic acids by catalytic hydrogenation. The derivatives prepared were screened as potential cytotoxic agents against Mes‐Sa human uterine sarcoma cell line.
Abstract New, green methods have been elaborated for the syntheses of α-hydroxyphosphonates and α-hydroxymethylenebisphosphonic derivatives (HMBPs, dronates). α-Hydroxyphosphonates were prepared via the Pudovik reaction, while the synthesis of HMBPs has been performed in the three-component reaction of carboxylic acids, phosphorus trichloride and phosphorus acid. Graphical Abstract
Organocatalytic enantioselective hydrophosphonylation of aldehydes
作者:Juan V. Alegre-Requena、Eugenia Marqués-López、Pablo J. Sanz Miguel、Raquel P. Herrera
DOI:10.1039/c3ob42403k
日期:——
our results concerning the first squaramide-catalysed hydrophosphonylation of aldehydes. In all cases, the reactions proceeded smoothly and cleanly under mild reaction conditions rendering final α-hydroxy phosphonates in very good yields and high enantioselectivities. It is one of the few organocatalytic examples of this reaction using aldehydes. It is the first time that diphenylphosphite (1e) has
active clusters, which encouraged us to synthesize further dibenzyl-α-diphenyl-OPP derivatives that elicited pronounced cell killing. Further structure–activity relationships showed the relevance of hydrophobicity and the position of substituents on the main benzene ring as determinants of toxicity. The most active analogs proved to be equally, or even more toxic to the multidrug resistant (MDR) cell line
Highly Enantioselective Aerobic Oxidation of α-Hydroxyphosphonates Catalyzed by Chiral Vanadyl(V) Methoxides Bearing <i>N</i>-Salicylidene-α-aminocarboxylates
作者:Vijay D. Pawar、Sampada Bettigeri、Shiue-Shien Weng、Jun-Qi Kao、Chien-Tien Chen
DOI:10.1021/ja060639o
日期:2006.5.1
An unprecedented vanadyl(V) methoxide complex 4 derived from 3,5-dibromo-N-salicylidene-l-tert-leucinate enables highly enantioselective aerobic oxidations of α-hydroxyphosphonates at ambient temperature with selectivity factors ranging from 3 to >99.