Phosphonate methane

C-P lyase has a broad snbstrate specificity and, for example, dimethyl phosphonate is degraded to methane, methylphenyl phosphonate to benzene, and the degradation of the widely nsed herbicide glyphosate may follow alternative pathways both of which involve C-P fission. 

Reactions and Properties of Phosphonic and Phosphinic Acids and their Derivatives.-A free radical mechanism has been proposed to account for the cleavage of the phosphorus-carbon bond in the alkylphosphonic acids (155) by E coli to give a mixture of alkane (methane only, from methylphosphonic acid) and terminal alkene. 

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... 

Figure 8.5 Synthesis of Phosphonated Silanes from Dimethyl methane phosphonate and Diphenyldichlorosilane (77)...

Phosphonate Diethyl Bromo-difluoro-methane ElOb,. 671 f-[CBr2F2 + (RO)3P]... 

Phosphonate Diethyl Dibromo-fluoro-methane ElOb,. 671 f. 

Thus, in the year 1950, an inventor named Tolkmith (IS) presented a patent application claiming a certain methane phosphonic chloride. The only utility stated for the compound was that it was of value as an intermediate for the preparation of more complex phosphorus derivatives and as a constituent of a parasiticide. The Patent Office Board of Appeals in its decision, held that the applicant s showing of utility did not comply with Section 112 of the patent statutes requiring that the manner and process of making and using the invention be described in such exact terms as to enable one skilled in the art to make and use the same. The board went on to say ... 

Durette et al. [74] have achieved the total synthesis of the hexadepsipeptide antibiotic L-156,602 128) using the mixed phosphonic anhydride method as key macrolactamization step. As shown in Scheme 43, treatment of the linear depsipeptide 126 with n-propylphosphonic anhydride and DMAP in dichloro-methane at high dilution afforded the macrocycle 127 in more than 57% yield. 

Phosphonic Acid Amino-phenyl-methan- E21e, 5725 [Nitron +... 

Phosphonate Dimethyl [(S)-Hydroxy (2-nitro-phenyl)-methane]- E21e, 5716 [CHO - CH(OH)—/ 0(0R)2]... 

ANTI)]-, ammonium, 26 24 C H2,Cl2PSis, Phosphonous dichloride, tris(trimcthylsilyl)methyl]-, 27 239 C, iH2iiSi), Methane, tris(trimethylsilyl)-, 27 238... 

Additional support for a free radical mechanism of the copper catalyzed reaction of red phosphorus with CH3CI or benzyl chloride comes from the isolation of methane, ethane, ethylene and propene in the CH3Cl-reaction and of trans stilbene and toluene in the PhCH2Cl-reaction, in addition to phosphonous dichlorides, RPCI2 (R = CH3, CgHjCHj ) 51) ... 

Evidence has been presented which appears to support an earlier hypothesis regarding the reaction between sodium dialkyl phosphites and polyhalogeno - methanes according to this, the phosphite salt and bromotrifluoromethane yield (difluoromethylene)bisphosphonic tetraesters through the abstraction of the bromonium cation by the phosphite anion, and this is followed by phosphorylation of the subsequent carbanion. The present evidence is based on the treatment of diethyl (dichlorofluoromethyl)phosphonate with sodium diethyl... 

Fluoromethylenation.11 Methods for fluoromethylcnation of ketones result in mixtures of (K)- and (Z)-vinyl fluorides, which are difficult to separate. A selective route involves reaction of the ketone with the carbanion of l-fluoro-l-(phenylsulfonyl)methane-phosphonate, prepared from fluoromethyl phenyl sulfones and diethyl chlorophosphate. The reaction provides mixtures of (E)- and (Z)-fluorovinyl sulfones, which can be separated by flash chromatography. Those products cannot be reduced by AI(Hg), but on treatment with tributyltin hydride (A1BN), they are converted into (fluorovinyl)stannancs with retention. Dcstannylation to vinyl fluorides can be effected with sodium methoxide in methanol or with CsF in methanolic ammonia.14... 

SULFICYLBIS (METHANE) (67-68-5) CjHjOS (CH3)2S0 Combustible liquid [explosion limits in air (vol %) 2.6 to 63.0 flashpoint 203°F/95°C oc autoignition temp 419°F/215°C Fire Rating 2]. Violent or explosive reaction with strong oxidizers, acryl halides, aryl halides and related compounds, alkali metals p-bromobenzoyl acetanilide, boron compounds, especially hydrides iodine pentafluoride, magnesium perchlorate, methyl bromide, perchloric acid, periodic acid, silver fluoride, sodium hydride, potassium permanganate. Forms powerfully explosive mixtures with metal salts of oxoacids [iron(III)nitrate, phosphonic acid, sodium perchlorate]. On small fires, use dry chemicals or COj extinguishers. 

The reaction of phosphorous esters and amides with polyhalogeno-methanes has been studied and used in a synthesis of phosphates. The reaction of diphenyl phosphorochloridate (103), produced in situ from diphenyl phosphonate and carbon tetrachloride, has been studied with various diamines. ... 

Essentially all the simple geminal di- or poly halides studied have been derivatives of methane. Reaction of diiodomethane (25,103) with triethyl phosphite proceeds normally, to furnish tetraethyl methanedi-phosphonate and iodomethanephosphonate. However, the reaction between carbon tetrachloride and trialkyl phosphite, first investigated by Kamai and Egorova (156,181), is catalyzed by peroxides or ultraviolet light, and accordingly it has been formulated by Kamai and Kharrasova (157) as a radical-chain process. 

Alkyl esters of phosphonous and phosphinous acid also react readily y with carbon tetrachloride, while analogous aryl esters, e.g., EtP(OPh)2, are resistant even at 160° (152,173). The reaction of bromotrichloro-methane with triethyl phosphite, which occurs smoothly at 80° to furnish dialkyl trichloromethylphosphonate in excellent yield (99%), is light catalyzed. Chloroform is unchanged in the presence of triethyl phosphite (98,156) even under drastic conditions, and diethyl dichloro-methylphosphonate is not produced unless a free radical initiator is present (118). 

---