Abstract A simple, efficient and environmentally benign method for the synthesis of α-hydroxyphosphonates by reaction of an aldehyde or a ketone, and trialkylphosphite is effectively accomplished under ultrasound irradiation and solvent-free and catalyst-free conditions. This rapid method produces α-hydroxyphosphonates in high yields and short reaction times. Graphical Abstract
acidic hydrolysis of α-hydroxybenzylphosphonates and a few related derivatives was monitored in order to determine the kinetics and to map the reactivity of the differently substituted phosphonates in hydrolysis. Electron-withdrawing substituents increased the rate, while electron-releasing ones slowed down the reaction. Both hydrolysis steps were characterized by pseudo-first-order rate constants. The
Synthesis and insecticidal activities of <i>O,O</i>-dialkyl-2-[3-bromo-1-(3-chloropyridin-2-yl)-1<i>H</i>-pyrazole-5-carbonyloxy] (aryl) methylphosphonates
作者:Wei Wang、Lie-Ping Wang、Bin-Ke Ning、Ming-Zhen Mao、Chao Xue、Hai-Yang Wang
DOI:10.1080/10426507.2016.1206103
日期:2016.10.2
A series of novel O,O-Dialkyl-2-[3-bromo-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carbonyloxy](aryl) methy-lphosphonates I-1-14 were designed and synthesized. The structures of all the title compounds were confirmed by H-1-NMR, C-13-NMR, P-31-NMR, IR and elemental analysis. Their insecticidal activities against Mythimna separata and Plutella xylostella were evaluated. The results of bioassays indicated that the title compounds exhibited 20-80% larvicidal activity against Mythimna separata at 1000mg/L.[GRAPHICS].
<i>N</i>-Heterocyclic Carbenes Catalyzed Phospho-Aldol Reaction of Aldehydes
作者:Lin He、Zhihua Cai、Xiaowei Ma、Guangfen Du
DOI:10.1002/cjoc.201300615
日期:2013.12
AbstractAn efficient phospho‐aldol reaction of aldehydes catalyzed by N‐heterocyclic carbenes (NHCs) has been developed. With 10 mol% stable NHC 1,3‐bis(2,6‐diisopropylphenyl)imidazol‐2‐ylidene, various aldehydes reacted with dialkylphosphites smoothly to provide α‐hydroxy phosphonates in 59% –99% yield. In this process, NHC was assumed to function as a carbon‐centered br?nsted base.
N-Heterocyclic Carbene Catalyzed Hydrophosphonylation of Aldehydes
作者:Lin He、Zhi-Hua Cai、Guang-Fen Du、Cheng-Zhi Gu、Bin Dai
DOI:10.1055/s-0030-1260045
日期:2011.7
N-Heterocycliccarbenecatalyzed Pudovik-type reaction of dimethyl trimethylsilyl phosphite and aldehydes for the construction of carbon-phosphorus bonds have been developed, providing α-hydroxyphosphonates in moderate to excellent yield. N-heterocycliccarbene - Pudovik-type reaction - α-hydroxyphosphonates - aldehydes - C-P bond