Dimethyl methyl phosphonate

The reaction of the aldehyde 174, prepared from D-glucose diethyl dithio-acetal by way of compounds 172 and 173, with lithium dimethyl methyl-phosphonate gave the adduct 175. Conversion of 175 into compound 176, followed by oxidation with dimethyl sulfoxide-oxalyl chloride, provided diketone 177. Cyclization of 177 with ethyldiisopropylamine gave the enone 178, which furnished compounds 179 and 180 on sodium borohydride reduction. 0-Desilylation, catalytic hydrogenation, 0-debenzyIation, and acetylation converted 179 into the pentaacetate 93 and 5a-carba-a-L-ido-pyranose pentaacetate (181). 

D-Ribonolactone is a convenient source of chiral cyclopentenones, acyclic structures, and oxacyclic systems, useful intermediates for the synthesis of biologically important molecules. Cyclopentenones derived from ribono-lactone have been employed for the synthesis of prostanoids and carbocyclic nucleosides. The cyclopentenone 280 was synthesized (265) from 2,3-0-cyclohexylidene-D-ribono-1,4-lactone (16b) by a threestep synthesis that involves successive periodate oxidation, glycosylation of the lactol with 2-propanol to give 279, and treatment of 279 with lithium dimethyl methyl-phosphonate. The enantiomer of 280 was prepared from D-mannose by converting it to the corresponding lactone, which was selectively protected at HO-2, HO-3 by acetalization. Likewise, the isopropylidene derivative 282 was obtained (266) via the intermediate unsaturated lactone 281, prepared from 16a. Reduction of 281 with di-tert-butoxy lithium aluminum hydride, followed by mesylation, gave 282. 

Dimethyl ether, 31 41, 244 formation in zeolites, 42 95-98 Dimethylethylbenzenes, 20 281 Dimethylindan, cyclization, 28 298, 299 Dimethylindene, cyclization, 28 298, 299 Dimethyl methyl phosphonate, catalytic decomposition, 35 159-160 Dimethylnaphthalenes, hydrogenation of, 18 64-102... 

A correlation can be made between the measured magnitude of the waveguide signals and the vapor pressures of the condensed vapors sensed. Three of the five polymer films tested showed extremely large responses to the simulant dimethyl methyl phosphonate (DUMP), and one of these films could detect DUMP vapor concentrations below the 20 ppm level. 

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). 

Delpuech et al. (106) examined the tetrahedral solvates of the beryllium cation with trimethyl phosphate (TMPA), dimethyl methyl phosphonate (DMMP), N,iV-dimethylamido-0,0 -dimethyl phosphate (DMADM P), bis-A,iV-dimethylamido-0-methyl phosphate (TMDAMP), and hexamethylphosphorotriamide (HMPT) by NMR including that of Be. The kinetics of ligand exchange ... 

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. 

The conducting sensor films are essentially thin films of materials that swell when exposed, causing resistance changes uniquely characteristic of a particular chemical. Since the process is reversible, these films can be used repeatedly. Their sensitivity has been demonstrated to be in the mid-ppb range for dimethyl methyl phosphonate and diisopropyl methyl phosphonate in air or exhaust fumes (Hopkins and Lewis, 2001). 

An important flame retardant additive is dimethyl methyl phosphonate (DMPP), a compound having a very high phosphorus content (Figure 18.1) [3, 17] ... 

TWA (time weighted value) permissible time averaged exposure concentration. DMMP, dimethyl methyl phosphonate DPGME, dipropylene glycol methyl ether. 

In an alternative approach to the use of DMS as a filter for ESI before a high-end MS, a low-resolution QMS was fitted with a DMS for real-time chemical analysis in the field. The instrument had a mass resolution of 140 with two stages of differential pumping and an electrodynamic ion funnel to transport the ion beam from ambient pressure to the MS. This prototype DMS-MS detected approximately 1 ppb of dimethyl methyl phosphonate (DMMP) as a simulent for chemical warfare agents. 

In given concentrations of sample vapor neutrals, spectra for product ions can be altered by control of temperature, and this was seen at cryogenic tanperature, at which ion clusters not usually observed in mobility spectra were formed and appeared in mobility spectra. For example, proton-bound trimers of alcohols were observed when temperatures were decreased to -20°C and dissociated at temperatures from -20°C to +10°C. " Increases in temperatures will lead to dissociation of complex ions, such as proton-bound trimers and proton-bound dimers. As temperature is increased, the intensity of peaks for protonated monomer increase, and the peak abundance of proton-bound dimers decreases. This has been developed and explored for dimethyl methyl phosphonate (DMMP), " amines, and ketones. For example, proton-bound dimers of alkyl amines underwent dissociation above -30°C on a 2- to 20-ms time scale, which is within the range of drift times for these ions. Consequently, the dissociation pathway can be observed as a distortion in the peak shape and baseline of a mobility spectrum since an ion entering the drift region as a proton-bound dimer dissociates to a protonated monomer before arriving at the detector. These studies permitted the determination of kinetics of dissociation for thermalized ions and illustrated that the appearance of an ion in a mobility spectrum is governed by ion lifetimes in comparison to ion residence times in drift tubes, and ion lifetimes are controlled by temperature. 

Positive gas phase ion chemistry governs the reactions of nerve agents or simulants such as DMMP (dimethyl methyl phosphonate) in the IMS ionization source. The main reaction pathway between the reactant ion that is a protonated dimer of the dopant R2H+(H20) [where R could be acetone (CH3)2CO] by an organophosphorus molecule G involves displacement of an R molecule by G to form a heterogeneous proton-bound dimer GRH+(H20) i (Equation 13.1). 

Rennet, calf Rennin Rennin, calf. See Rennet Reofiam DMMP. See Dimethyl methyl phosphonate... 

The most common simulant of phosphorus-containing CWAs, such as VX, is dimethyl methyl phosphonate (DMMP). The adsorptive and reactive... 

The inks are prepared by mixing an epoxy resin (Epon 826 epoxy resin) with dimethyl methyl phosphonate, nanoclay platelets (Cloisite 30b), silicon carbide whiskers (SI-TUFF SC-050), and milled carbon fibers (Dialead K223HM). Further, an imidazole-based ionic liquid is employed as a latent curing agent (Basionics VS03) (31). 

Saxena et al. studied the adsorption of dimethyl methyl phosphonate (DMMP) as a stimulant for Sarin, which is a highly toxic warfare gas agent. The adsorption was carried out on an activated carbon, a whetlerite and activated carbon impregnated with copper hexafluorocacetylacetonate (1) copper trifluoro acetyl-acetonate and a copper oxime. The adsorption isotherms are Type 1 of the BET classification and show maximum adsorption in the case of activated carbon (1). The amount adsorbed was 68.5 weight percent on (1). The adsorption involved both physisorption and chemisorption. TGA and IR studies of DMMP loaded activated carbons, and mass spectric analysis of the decomposition products showed that the decomposition products were methyl methyl phosponic acid and methylphosphonic acid. 

Photocatalytic activity has also been observed with some of these compounds. For instance, titanium dioxide nanoparticles were able to degrade 2-chloroethyl sulfide (mustard) in liquid and gas phase, a series of warfare agents like diethyl sulfide, dimethyl methyl phosphonate, diethyl phosphoramidate, pinacolyl methyl-phosphonate, and butylaminoethanthiol, and pesticides such as lindane, methyl parathion, and dichlorvos upon exposure to ultraviolet light (Vigo and Thibodeaux, 2001 Sundarrajan et al., 2010). Zinc oxide nanoparticles were incorporated into polymers used to produce electrospun coating on cotton fabrics and provided them with photocatalytic-activated antimicrobial properties (Munoz-BonUla and Femandez-Garcia, 2012). 

PI Conductometric (RT) C black/vinyl acetate (direct writing) Dimethyl methyl-phosphonate Marinov et al. (2007)... 

Chemical Name Dimethyl methyl phosphonate Physical Appearance Colorless liquid Phosphorus Content Wt% 25.0 Applications ... 

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