Dimethyl vinylphosphonate

In Michael-type reactions, unsaturated phosphorus substrates such as dimethyl vinylphosphonate and tetraethyl ethenylidenediphosphonate undergo addition of carbanions from ethyl... 

Scheme 3.3 Thiol-ene reaction with dimethyl vinylphosphonate.

PVPA can also be obtained by hydrolysis of poly(dimethyl vinylphosphonate) (PDMVP), which was synthesized both through free radical and anionic polymerization. Structural analysis revealed that PDMVP obtained by anionic polymerization is isotactic-rich. 

Poly(VPA-co-slyrene) has been obtained by free radical polymerization of styrene and dimethyl vinylphosphonate in the bulk, followed by hydrolysis." The resulting copolymers, shown in Scheme 13.1d, had a low VPA content (5-14 mol%). Despite the difference between the reactivity ratios of the comonomers, poly(slyrene-co-dimethyl vinylphosphonate) presented only a single glass transition temperature, indicating a near random connectivity between the styrene and dimethyl vinylphosphonate units in the copolymers. The copolymers were stable under air and inert atmosphere... 

Phosphonates. The principal synthetic routes include addition and condensation methods. Although a large number of vinyl and diene phosphonate monomers have been described in the literature (2,5,7,62), only bis(2-chloroethyl) vinylphosphonate (Akzo-Nobel s Fyrol Bis-Beta monomer), vinylphosphonic acid (Clariant), and dimethyl vinylphosphonate (Clariant) have been offered commercially. The diethyl vinylphosphonate is available in laboratory quantities. 

Sato T, Hasegawa M, Seno M, Hirano T (2008) Radical polymerization behavior of dimethyl vinylphosphonate homopolymerization and copolymerization with trimethoxyvinylsilane. J Appl Polym Sci 109 3746-3752... 

Oligomeric Vinylphosphonate. A water-soluble oligomer, Fyrol 76 [41222-33-7] is produced by reaction of bis(2-chloroethyl) vinylphosphonate and dimethyl methylphosphonate with elimination of all the chlorine as methyl chloride (127,128). This Hquid, containing 22.5% P, is curable by free-radical initiation, on cotton or other fabrics. Nitrogen components, such as A/-methylolacrylamide or methylolmelamines, are usually included in the finish, which can be durable to multiple launderings (129,130). 

Diazoalkanes add readily to the double bond of esters of vinylphosphonic acid, giving the pyrazoline derivatives (100), which can lose nitrogen to give esters of cyclopropylphosphonic acids. In a similar reaction, acyl-phosphonic acid esters (101) were converted to epoxy-derivatives (102). A -Phenylsydnone adds to diethyl prop-l-ynephosphonate, giving the pyra-zole (103). The addition of cyclopentadiene to dimethyl vinyl phosphate leads to an exojendo quotient of 1.2, but with hexachlorocyclopentadiene only e/ii/o-isomer is formed. ... 

One embodiment of this general reaction led to a product which was commercially produced for several years by Stauffer as Fyrol 76 (9), a copolycondensation product of dimethyl methyl-phosphonate with bis(2-chloroethyl) vinylphosphonate. The features of Fyrol 76 were high phosphorus content (20%), water solubility, and ability to be polymerized by means of a radical initiator to a crosslinked polymer. A related polycondensation product was developed from tris(2-chloroethyl) phosphate and dimethyl methylphosphonate. By control of the reagents and procedure used for neutralization, these oligomeric products were produced with primary alcohol functional groups (7). 

Fyrol 76 is a vinylphosphonate/methylphosphonate oligomer and is water soluble. It was developed by Dr. Edward Weil and his group (22,25). It is prepared by the thermal condensation of bis(2-chloroethyl) vinylphosphonate with dimethyl methyl-phosphonate as shown in the idealized equation 29. 

Dimethyl l-(Methoxycarbonyl)vinylphosphonate and Diethyl 1 -(Ethoxycarbonyl) vinylphosphonate... 

Cabioch. J.-L.. Pellerin, B., and Denis, J.-M., Synthesis of piimary a-chlorophosphines by a chemoselective reduction of a-chlorophosphonates, Phosphorus, Siiifur Silicon Relat. Elem., 44, 27, 1989. Kuinai aswainy, S., Selvi, R.S., and Swamy, K.C.K., Syntliesis of new a-hydroxy-, a-halogeno- and vinylphosphonates derived from 5,5-dimethyl-l,3,2-dioxaphosphinan-2-one, Synthesis, 207, 1997. Diehr, H.-J., and Fuchs, R.A., Chlorostyrylcyclopropanecarboxylic acid derivatives, Bayer, Eur. Patent Appl. EP 0006205, 1980 Chem. Abstr. 92, 215078, 1980. 

The Pd-catalyzed hydrophosphonylation of terminal alkynes with dialkyl phospliites seems destined to become the method of choice for tlie synthesis of a-substituted vinylphosphonates. The reaction proceeds by regioselective attack of dialkyl phosphite at the internal carbon of the triple bond (Scheme 6.37). Thus, 5-cyano-l-pentyne reacts efficiently with dimethyl phosphite in the presence of cZv-PdMe2(PPh2Me)2 affording dimethyl l-(3-cyanopropyl)vinylphosphonate in 94% yield. In the absence of catalyst, the hydrophosphonylation product is not detected. ... 

Trimethyl phosphite does not react with chloroacetyl chloride through a Michaelis-Arbu-zov/Perkow reaction sequence. It gives an acylpseudophosphonium salt, which, in turn, reacts readily with trimethyl phosphite to give a new adduct. Subsequent warming affords dealkylation to give the final dimethyl l-(dimethoxyphosphinyloxy)vinylphosphonate (Scheme 7.3). More interesting from the mechanistic standpoint is the use of diethyl trimethylsilyl phosphite. In reaction with chloroacetyl chloride at 30°C, the initial adduct loses MejSiCl rapidly to give diethyl 2-chloroacetylphosphonate in 37% yield." ... 

Vinylphosphonates of cytosine, uracil and ara-C have been prepared by Wittig reactions, and intermediates in these syntheses were hydroxylated using AD-mix-a to give the product 196 and the related derivatives of uridine and cytosine, Geminal hydroxyphosphonates 197 (R = Me or H, and with all four nucleobases) have been prepared by addition of dimethyl phosphite or tris-Tms phosphite to 5 -aldehydes. Similar products were obtained from 2, 3 -0-iso-propylidene ribonucleosides, except in the case of adenosine. NMR studies indicated that the major diastereoisomer formed in each case had 5 -R-stereochemistry, and in some cases this was produced in up to 90% d.e. ... 

The phosphorus can also be introduced in the form of a vinylphospho-nate for copolymerization with styrene in the curing step. Polyesters of this type, with bis(2-chloroethyl) vinylphosphonate as part of the cross-linking system, were marketed for a time (173). The only use of phosphorus compounds in any significant volume in polyester resins has been that of triethyl phosphate or dimethyl methylphosphonate for viscosity reduction and flame retardancy in filled-polyester, sheet-molding compositions. 

The development of transformations that can be carried out under air instead and do not require the use of gloveboxes or vacuum manifolds is extremely practical due to their operational simplicity. To this end, a potentially valuable microwave-assisted formation of vinylphosphonates was reported by Larhed (Scheme 4.338) [391]. Using palladium acetate as the catalyst and 2,9-dimethyl-l,10-phenanthroline (dmphen) as the supporting... 

Kumaraswamy S, Selvi RS, Swamy KK (1997) Synthesis of new a-hydroxy-, a-halogeno- and vinylphosphonates derived from 5,5-dimethyl-l,3,2-dioxaphosphinane-2-one. Synthesis 1997 207-212... 

Yokomatsu T, Yoshida Y, Suemune K, Yamagishi T, Shibuya S (1995) Enantioselective synthesis of threo-a,jS-dihydroxyphosphonates by asymmetric dihydroxylation of vinylphosphonates. An application to the stereocontrolled synthesis of (4S,5S)-4-diethylphosphono-5-hydroxymethyl-2,2-dimethyl-l,3-dioxolane. Tetrahedron Asym 6 365-368... 

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