Vinyl phosphonic ester

Loreto, M.A., Pompili, C., and Tardella, P.A., a-Methylene P-amino phosphonic ester derivatives by amination of (l-trimethylsilanylmethyl-vinyl) phosphonic esters. Tetrahedron. 57, 4423, 2001. 

Among phosphonate esters (170) used in olefin synthesis were those with R = S-CeHi-Br-/ , S02 C6H4-Br-A CO-NHR, and S CHa CEi-XHa. The allyl vinyl thio-ethers (171) obtained using the last of these gave a-allyl-aldehydes on pyrolysis in the presence of red mercuric oxide. 

Synthesis of isomeric chiral protected (63 )-6-amino-hexahydro-2,7-dioxopyrazolo[l,2- ]pyrazole-l-carboxylic acid 280 is shown in Scheme 36. Crude vinyl phosphonate 275, obtained by treatment of diethyl allyloxycarbonylmethyl-phosphonate with acetic anhydride and tetramethyl diaminomethane as a formaldehyde equivalent, was used in the Michael addition to chiral 4-(f-butoxycarbonylamino)pyrazolidin-3-one 272. The Michael addition is run in dichloro-methane followed by addition of f-butyl oxalyl chloride and 2 equiv of Huning s base in the same pot to provide 276 in 58% yield. The allyl ester is deprotected using palladium catalysis to give the corresponding acid 277, which is... 

Two reports are available on the rearrangement of mixed vinyl phosphite esters to produce phosphonate diesters in moderate yield.94 95 In both instances, the vinyl phosphite esters were prepared by reaction of the dialkyl phosphorous chloride with highly enolized carbonyl compounds. The mixed ester products undergo thermal rearrangement to the phosphonate diesters (Figure 6.25). 

Vinyl phosphonates have been used in the construction of valerenic acid terpenoids 169 (Scheme 42).101 Both five-and six-membered rings can be formed via the vinyl phosphonate Alder-ene reaction which can be catalyzed by a variety of Lewis acids. The resulting structures 167 are suitable for Wittig-Horner reaction to give diene 168. Subsequent reactions access valerenic acid terpenoids 169. The chirality of the carbon bearing the phosphonate and ester is transferred, but is subsequently lost in the Wittig-Horner step. 

Phosphinimines, 50, 109 Uf-Phosphinolin-4-one, 2,3-dihydro, 1-phenyl, 53, 102 Phosphonic acid, 2-(cyclo-hexylamino)vinyl-, diethyl ester, 53, 44... 

A wide range of a,P-unsaturated acceptors work well under standard reaction conditions with pre-catalyst 75c (Table 7). Acceptors include a,P-unsaturated esters, amides, alkyl ketones, and phosphine oxides, many of which provide the products in greater than 90% ee [68, 69], a,P-Unsaturated phenyl ketones, nitriles, and thioesters also work, albeit with lower enantioselectivity. The scope has been extended to include a variety of vinyl phosphonate precursors providing good chemical yields and moderate to high enantioselectivity (entries 9 and 10). 

More sophisticated functions, such as acyllactam vinyl silane , isocyanate phosphonic ester -2, etc. have been attached at the end of polymer chains, in nearly quantitative yields. Also polymers fitted with dyes or fluorescent groups at chain ends have been synthesized. ... 

DIETHYL 2-(CYCLOHEXYLAMINO)VINYLPHOSPHONATE (Phosphonic acid, [2-(cyclohexylamino)vinyl]-diethyl ester)... 

Grubbs used (4a) to efficiently install functional groups that might otherwise be added via C H activation or allylic oxidation pathways (Scheme 12). Among the breadth of compound types accessible through these cross metathesis strategies were substituted vinyl-phosphonic, boronic, and carbonyl esters, which were synthesized in good to excellent yields. ... 

The syntheses of carbocyclic analogs of phosphononucleosides (29) and (30a-c) have been reported. Phosphonic acid (29) was obtained by introduction of the benzoylated thymine on the 2(4-hydroxycyclopent-2-enyl)ethyl phosphonic acid diisopropyl ester under Mitsunobu conditions while (30a-c) were prepared by building-up the base around a phosphono-cyclopentylamine moi-ety. The vinylphosphonate derivatives of uridine, cytidine and cytosine ara-binoside (31a-c) have been prepared by Wittig condensation of [(diethoxyphos-phinyl)methylidene]triphenylphosphorane with the appropriately protected 5-aldehydic nucleoside derivatives. Dihydroxylation of the novel vinyl phosphon-ates offered the dihydroxylated phosphonate derivatives (32a-c). Each of these novel compounds was evaluated as substrates for the enzyme nucleotide monophosphate kinase, and their toxicity to K562 cells. All analogues were found to be poorly phosphorylated by the kinase and exhibited poor in vivo toxicity. ... 

Classification Nonaromatic phosphorus compd. Empirical C9H21O3P Formula [(CH3)2CH]3P03 Properties Colorless liq. char, odor misc. with most common org. soivs. insol. in water m.w. 208.27 dens. 0.914 (20/4 C) b.p. 94-96 C (50 mm) flash pt. (COC) 73.9 C ref. index 1.4110 Toxicology LD50 (oral, rat) 167 mg/kg, (IP, mouse) 500 mg/kg, (skin, rabbit) > 2 g/kg poison by ing. mod. toxic by IP route irritant mutagenic data TSCA listed Precaution Combustible hydrolyzes slowly in water minimize exposure to air Hazardous Decomp. Prods. Heated to decomp., emits toxic fumes of POx Storage Moisture-sensitive Uses Intermediate for insecticides, pharmaceuticals, mfg. of phosphonate esters, acids, and salts component of vinyl stabilizers lubricant additive specialty solvent heat and light stabilizer, antioxidant, metal chelator for polyester... 

Other Michael Acceptors, other Michael acceptors such as malei-mides [27], vinyl phosphonates [28], alkylidine malonates [29], ethyl 2-(dithox-yphosphoryl)acrylate [30], a-keto-a,(3-unsaturated esters [31], -Y-keto a, 3-unsaturated esters [32], and a,(3-unsaturated thiol esters [33] were also applicable in the enantioselective Michael reactions with aldehydes (Scheme 5.15). 

Conjugated dienes undergo hydroperfluoroalkylation with perfluoroalkyl iodides and zinc in the presence of titanium catalysts 02 Yields are moderate to good (52-74%) but stereoselectivity is low. From allylic halides functionalized on the a-vinylic position (TMS, carboxylate, phosphonate), additions to terminal alkynes provide functional dienes, used in further synthetic reactions leading to lactones and carboxylic or phosphonic esters.228... 

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