a-Hydroxy phosphonates have attracted considerable attention owing to their critical roles in anticancer drugs, plant growth regulators, and enzyme inhibitors. [1] The traditional way to synthesize a-hydroxy phosphonates is an addition reaction of monobasic phosphorus (the Pudovik reaction) or odorous trialkyl phosphite (the Abramov reaction) to an aldehyde or ketone. [2] Moreover, the reactions based on phosphonate derivatives such as oxidation of alkyl phosphonates [3] or reduction or addition of keto phosphonates [4] have also been found to be effective methods to form a-hydroxy phosphonates. Recently, great efforts have been made to develop metal-catalytic [5] or metal-free [6] syntheses of ahydroxy phosphonates involving the condensation of Hphosphonates with carbonyls.Catalytic functionalization of alcohols and ethers have garnered much interest owing to the ease of generating carbon-carbon [7] and carbon-heteroatom bonds. [8] Typical catalysts for this reaction are Ru, [9] Ir, [10] Pd, [11] Cu, [8a] and Fe [8c, 12] ; furthermore, it has been accomplished under transition-metal-free conditions. [13] Although many heteroatomic (oxygen, nitrogen) nucleophilic reagents are used in the alkylation catalyzed by these complexes, H-phosphonates as the substrates have not been investigated for the preparation of a-hydroxy phosphonates.Herein, we present a facile method for the phosphonation of alcohols or ethers catalyzed by CuCl 2 /TBHP (tert-butyl hydroperoxide) with moderate to good yields. Compared with aldehydes, the corresponding alcohols are readily available, highly stable, cheaper, and less toxic. The direct condensation of simple H-phosphonates with alcohols is found to be a more environmentally friendly route than reactions in which aldehydes and trivalent phosphorus compounds are used as reagents.The a-hydroxyphosphonation reaction catalyzed by copper depends greatly on the reaction conditions. The scope and limitation of the reaction is illustrated in Table 1, with benzyl alcohol (1 a) and diisopropyl H-phosphonate (2 a) as selected substrates. The yield of 3 a was determined by 31 P NMR spectroscopy. Treament of 2 a (1.0 mmol, 31 P NMR: d = 7.0 ppm) with 1 a (1.2 mmol) in the presence of CuCl 2 (5 mol %) with TBHP (1.2 mmol) and K 2 CO 3 (0.6 mmol) in 1,2-dichloroethane (DCE) at 80 8C for 24 hours produced diisopropyl a-hydroxybenzyl phosphonate (3 a, 31 P NMR: d = 19.5 ppm) in 80 % yield (Table 1, [a] Z.

Cyclic acylphosphoramidates (2-hydroxy-2-oxy-1,3,2-oxazaphospholidine-5-ones, CAPAs) are phosphate-activated amino acids possessing both a carboxyl-phosphoryl anhydride and a phosphoramidate bond in a ring. They structurally resemble NCAs (amino acid N-carboxyanhydrides, Leuchs' anhydrides), which have been extensively investigated. By contrast, the chemistry of CAPAs has remained almost unexplored since it was proposed in a prebiotic reaction of inorganic polyphosphates (Polyps) with amino acids. In the present work, the bielectrophilicity of alpha-CAPAs (Gly-CAPA, Ala-CAPA) was identified by isotopic analysis (O-18, N-15) and further proved by trapping alpha-CAPA with nucleophiles such as water, amino acids, phosphate and methanol in alkaline media, which yielded N-phosphoamino acids and peptide phosphoanhydride and phosphate ester derivatives. By comparison with the reactivity of NCAs, the bielectrophilicity of CAPAs indicates that CAPAs can provide rich chemistry. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weiriheim, Germany, 2009)Ministry of Science and Technology [2006DFA43030]; Chinese National Natural Science Foundation [20732004

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Copper-Catalyzed Synthesis of α-Hydroxy Phosphonates from H-Phosphonates and Alcohols or Ethers. -(ZHAO, Z.; XUE, W.; GAO, Y.; TANG*, G.; ZHAO, Y.; Chem. -Asian J. 8 (2013) 4, 713-716, http://dx.