Vinyl phosphorus compounds

Mukaiyama-Michael addition of a chiral ketene acetal to nonprochiral vinyl ketones gives products of 72-75% ee.145 A chirally modified glycine derivative (Schiff-base) adds to vinylic phosphorus compounds to yield, after hydrolysis, products with 54-85% ee.146 Another chiral glycine equivalent was used for the preparation of homochiral proline derivatives via diastereoselective addition to a,3-unsatu-rated aldehydes and ketones.147-148... 

There are several other examples of C-chiral hydroxy phosphorus compounds which were obtained in enantiomerically enriched forms using enzymatic methodology. Thus, a 5-l-diethylphosphonomethyl-2-hydroxycyclohexane 48 was resolved into enantiomers by enzymatic acetylation the highest enantioselectivity was achieved using lipase PS in THF or lipase AK without solvent and vinyl acetate as the acetylating agent (Equation 26). ... 

Altoff, W., Fild, M., Rieck, H.-R, and Schmutzler, R., Synthesis and NMR spectroscopic studies of phosphorus compounds with vinyl and ethynyl groups, Chem. Ber., Ill, 1845, 1978. 

The 1 1 addition of RPH2 to a vinylphosphonate (Equation 4a) proceeds effectively under base-catalyzed conditions in contrast to the 1 1 addition of RPH2 to a vinylphosphine (Equation 3). This point can be related to the basicity of the anions involved as intermediates in the Michael-type addition of phosphorus-hydrogen compounds to vinyl-phosphorus derivatives (12). 

This is particularly so with a-heterosubstituted derivatives, as shown by a number of recent examples in which oxide derived ylids have been found to give vinyl derivatives in circumstances where the corresponding phosphonate derived ylids do not (2-5). It was therefore decided to prepare the parent (unsubstituted) a-methoxy-allyl phosphorus compounds 1, 2 and 3, in order to investigate their Wittig-type chemistry. 

Pentaerythritol is used in self-extinguishing, nondripping, flame-retardant compositions with a variety of polymers, including olefins, vinyl acetate and alcohols, methyl methacrylate, and urethanes. Phosphorus compounds are added to the formulation of these materials. When exposed to fire, a thick foam is produced, forming a fire-resistant barrier (see FLAME RETARDANTS) (84—86). 

Sulfonyl azides add to trivalent phosphorus compounds, strained alkenes, e.g. norbornene, enamines and vinyl ethers at comparatively low temperatures. In each case, the initial adduct decomposes on warming with loss of nitrogen, as indicated in Scheme 64. 

At low temperatures, trialkyl phosphites and chloral give the 1,4,2-dioxaphos-pholans (96), which decompose above —10 °C to give the vinyl phosphates (97). 1,4,2-Dioxaphospholans are also formed from benzaldehyde and the tervalent phosphorus compounds (98). ... 

When I started working at Victor Chemical Works in 1942, my boss. Dr. Howard Adler, wanted me to look into the possibility of making some phosphorus-containing polymers. It is known that organic phosphorus compounds have flame retarding properties. To put things in the proper historical perspective, at that time vinyl polymers and nylon were relatively new commercial products. (Polymers such as the ethylene terephthalate polyesters and polycarbonate were not introduced to the market place until many years later.)... 

Phosphorus-containing enamines have been prepared by phosphorylation of N-vinyl substituted tertiary amides, lactams and cyclic imides with phosphorus pentachloride ". Addition of amines to diphosphoryl alkynes has been described. Addition of RR NH [R = H, Ri = Me, cyclohexyl, PhCH2 RR = (CHj) to (Et0)2P(0)C=CP(0K0Et2)2 in CH2CI2 at 25 °C gave 93-100% of (Et0)2P(0)C(NRRi)=CHP(0)(0Et2)2 . Speziale and coworkers have studied the reactions of phosphorus compounds with trichloroacetamides. 

Reaction with phosphorus compounds. Hydrozirconation of vinyl(diphenyl)-phosphine at C-l is feasible, while ring cleavage of l-phenylphospha-3-cyclopentene to give homoallylic phosphines is observed. (l-Benzyl-3-pyrroline and dihydro-furan also undergo similar cleavage.)... 

Various phosphorus compounds can be synthesized by P-H bond addition to unsaturated organic molecules (alkynes, alkenes, dienes, aldehydes and imines). The target products are in demand as biologically active compounds [8-26], useful compounds in nucleic acid chemistry [27-31], versatile reagents in synthesis [32-36] and building blocks in polymer sciences [37-43]. In the area of biologically active compounds antifungal and antibacterial properties of vinyl phospho-nates were considered as well as their anticancer and antiviral activity was evaluated [44 7]. Practical application includes utilization of phosphorus compounds in fuel cell membranes, optical materials and flame retardants [48-55]. 

Preparation of vinyl organo-phosphorus compounds (1972), US Patent no 3673285. Chem Abstr (1972) 77, no 140290J... 

Nickel and palladium complexes also catalyze the formation of the carbon-phosphorus bonds in phosphorus(V) and phosphorus(III) compounds. Indeed, this chemistry has become a common way to prepare phosphine ligands by the catalytic formation of phosphine oxides and subsequent reduction, by the formation of phosphine boranes and subsequent decomplexation, or by the formation of phosphines directly. The catalytic formation of both aryl and vinyl carbon phosphorus bonds has been accomplished. 

The present effort is intended to provide an update of the earlier edition, bringing to the chemist in concise form advances in the approaches to C-P bond formation previously discussed, as well as several other aspects of C-P bond formation. These latter aspects include the generation of organophosphorus compounds from elemental phosphorus (of particular industrial interest for purposes of cost containment) advances in the preparation of phosphoranes, including the use of transient oxophosphoranes as intermediates in organophosphorus compound syntheses and new approaches toward the preparation of compounds with aromatic and vinylic carbon-phosphorus bonds. 

A -Unsubstituted 1,2,4-diazaphospholes (4) undergo A -alkylation by reaction with alkyl vinyl ether, sulfur ylides, and diazo compounds <95HAC403>. They react with acyl chlorides in a 2 1 molar ratio to give a mixture of the A -acylated diazaphosphole and the diazaphosphole hydrochloride. Preparative A -acyclation is achieved in presence of a tertiary amine. Sulfonyl chlorides and phosphorus trichloride also give A -substitution reactions (Scheme 2) <87TH 422-01 >. 

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