Organotin phosphonates

Freireich et al. " described the synthesis of poly(organotin phosphonates) from the reaction of dialkyltin dichlorides, tetralkyldichlorodistannoxanes, or hexaalkydichlorotristannoxanes with the disodium salt of phenylphosphonic acid, 65. 

Concerning the oxygen-containing bidentate ligands [R E02+ ] and MC, discrete dimeric, tetrameric and hexameric ring assemblies have been reported for organotin carboxylate, phosphinate, phosphonate monoester, phosphate diester, " sulfonate, and tungstate derivatives. 

Diethyl H-phosphonate forms a a-donor complex with uranyl nitrate U02(N03)2 similar to those already described for BXj and organotin halides [419]. 

Like carboxylates, numerous organotin derivatives ( esters ) of inorganic and element-organic acids (carbonates, nitrates, phosphates, phosphonates, phosphi-nates and their arsenic analogs, sulfonates, sulfinates, etc.), are characterized by supramolecular self-assembly in solution and/or supramolecular self-organization in solid state. 

The transfonnations of gm-dihalocyclopropanes are synthetically useful because the cyclopropanes are readily prepared by the addition of dihalocarbene to olefins. In most of dehalogenation reactions to monohalocyclopropanes, the reagents are limited to metallic reductants such as organotin hydride, lithium aluminum hydride, sodium borohydride, Grignard reagent, and zinc-copper couple [1-9]. A versatile method for the reduction of gm-dibromocyclopropanes 3 with an organic reductant is achieved by use of diethyl phosphonate (commercially named diethyl phosphite) and triethylamine to give the monobromocyclopropanes 4 (Scheme 2.2) [10]. 

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