Phosphine, methyl

Organophosphorus compounds. Phosphorus-carbon bond fonnation takes place by the reaction of various phosphorus compounds containing a P—H bond with halides or tritlates. Alkylaryl- or alkenylalkylphosphinates are prepared from alkylphosphinate[638]. The optically active isopropyl alkenyl-methylphosphinate 778 is prepared from isopropyl methylphosphinate with retention[639]. The monoaryl and symmetrical and asymmetric diarylphosphi-nates 780, 781, and 782 are prepared by the reaction of the unstable methyl phosphinate 779 with different amounts of aryl iodides. Tnmethyl orthoformate is added to stabilize the methyl phosphinate[640]. 

Numerous diamines and aromatic dianhydrides have been investigated. WhoUy aromatic Pis have been stmctiirally modified by incorporating various functional groups, such as ether, carbonyl, sulfide, sulfone, methylene, isopropjlidene, perfluoroisopropyUdene, bipyridyls, sdoxane, methyl phosphine oxide, or various combinations of these, into the polymer backbone to achieve improved properties. The chemistry and apphcations of Pis have been described in several review articles (4). 

Diethyl ether Methyl phosphine Vinylidene chloride... 

The [l,2]-a rearrangement of phosphinothioates into (alkylsulfanyl-methyl)phosphine oxides using a chiral phosphinoyl group has also been reported (see Sect. 5.1.1.). 

An interesting [1,3]-Si shift from nitrogen to nitrogen has been observed in the Staudinger imination reaction of AT-ferf-butyl-iV-trimethylsilyl-P,P-di-methyl phosphinous amide 32 with trimethylsilylazide [137]. The steric bulk provided by the tert-hutjl group seems to determine the direction of the silyl shift (Scheme 32). 

Trimethylantimony Nickel-titanium Ethyidi methyl phosphine ... 

Optically active O-isopropyl (5)-( — )-methylphosphinothioate (136) has been prepared for the first time by reaction of isopropy (/ )-(- )-methyl-phosphinate (137) with P4S10. The retention of configuration at phosphorus during this conversion was established by the formation of the two enantiomers, (138) and (139), of O-isopropyl 5-phenyl methylphosphonodithioate by separate routes of known stereochemistry. 

More recently, Shibuya used the ALB catalyst for addition of methyl phosphinate to aldehydes (Scheme 5-39). 

Scheme 5-39 Asymmetric addition of methyl phosphinate to aldehydes using heterobimetallic BINOLcatalysts LLB = La/Li/BINOL, LPB = La/K/BINOL, ALB = AI/Li/BINOL...

The reaction of (31 X = K) with chlorotrimethylstannane yields the stannylphosphine (31 X = SnMe3), which on subsequent treatment with dichloro(methyl)phosphine, is converted into the... 

Valence Isomerism. Restricted Rotation and Permutational Isomer i sm. - The variable temperature spectra of bicyclic tetraphosphines (29) has been analysed in terms of valence isomerism involving the corresponding two coordinate open-chain isomers.62 A report on ab initio MO calculations of the inversion barriers for a series of methyl phosphines includes a discussion of the electronic consequences of steric effects.63 Inversion barriers of 1,2-diphosphinobenzenes are in the range 100 - 110 kJ mol". 66 The ring inversion barrier for a dibenzophosphorin has also been measured.63... 

Ethoxy(ethylthio)(methyl)phosphine Oxide C01-D139... 

Diethyl 7V,./V-dimethylaminomethylenemalonate was obtained in the reaction of di-fm-butyl[bis(dimethylamino)methyl]phosphine and diethyl malonate at 80-100°C for 1 hr in 45% yield (88ZOB1445 89ZOB2206). 

Biphilic Reactions.—A most thorough investigation into the cycloaddition of buta-1,3-diene with dichloro(methyl)phosphine (30) has revealed some of the factors which influence the composition of the final products.32 Thus the A3-phospholen 1-oxide (31) is the product of the cycloaddition at room temperature, but at 90 °C the isomeric A2-phospholen 1-oxide (32) predominates after work-up. The yields of (31) and (32) are improved by a new work-up involving methanolysis rather than hydrolysis of the intermediate salts.32... 

Synthetic studies of various cyclic phosphine oxides continue to be published. Thus a methanolic work-up leads to an 88% yield of 1-methylphospholen 1-oxides (6) from dichloro(methyl)phosphine, and detailed S1P n.m.r. and mass spectra have been described.10 The oxides (7) and (8) have been prepared11 as shown. Structural... 

Comparison of carbon-13 shifts of methyl phosphines and methyl substituted methanes... 

Some examples of two-bond P-X-H couplings (Hz), X = C, Ge and Si, in methyl phosphine derivatives... 

BMIs and maleimide-terminated prepolymers have been considered for systems with improved Fire, Smoke and Toxicity properties. Of particular interest are phosphorous-containing bismaleimides because they provide high Limiting Oxigen Index (LOI) values (30). 3,3 -bis(maleimidophenyl) methyl phosphine oxide is such a compound (Fig. 7). 

Trimethylsilylimino) (trimethylsilyl) [tris(dimethylamino)phosphoranylidene] methyl phosphine (64), produced by the reaction of [(dichlorophosphanyl)methyl]tris (dimethylamino)phosphonium tetraphenylborate with sodium bis(trimethylsilyl)amide,... 

Ethyl Phenyl[(tritylamino)methyl]phosphinate (67, R2= Ph R3=Et) (Table 10, Entry 1) Typical Procedure 33 ... 

Numerous alkyl and aryl phosphine, arsine and stibine compounds are described as being silver solvents. Examples are tris(p-hydroxyphenyl)phosphine and bis(2-carboxyethyl)methyl-phosphine.72... 

Bis[diazo(trimethylsilyl)methyl] phosphines 239 loose only one equivalent of dinitrogen on warming and are transformed into l,2,4(k3)-diazaphospholes 240139 (equation 81). It is obvious to explain this cyclization by intramolecular ketazine formation of a diazocarbene intermediate, but in light of the preceding discussion, speculations about the bond state of this phosphinocarbene (phosphavinyl ylide or phosphaacetylene) are allowed. 

Litvina, M.N., Chmutova, M.K., Myasoedov, B.F., Kabachnik, M.1.1996. Extraction and separation factors of lanthanides and americium in aqueous nitric acid- diaryl(dialkyl)-(dialkylcarbamoyl-methyl)phosphine oxide systems. Radiochemistry 38 (6) 494 -99. 

Bidentate oxygen-donor extractants include the neutral diamide compounds, such as the malonamides used in the French DIAMEX and DIAMEX-SANEX processes, RR N(C=0)-CHR"-(C=0)NRR the bisphosphine oxides, RR (P=0)- CIIR"-(P=0) RR the carbamoyl-(methyl)-phosphinates, R0R 0(P=0)-(CI I On o 0rr(C=0)NRR or the more efficient carbamoyl-methyl-phosphine oxides, RR (P=0)-CHR"-(C=0)... 

FIG U RE 3.1 n-Octyl-phenyl-W, W -di(/so )butyl-carbamoyl-methyl phosphine oxide (CMPO) used in the TRUEX process. 

Carbamoyl methyl Phosphine Oxide Derivatives The physicochemical properties of various aryl derivatives of CMPO have been investigated at the Vernadsky Institute of Geochemistry and Analytical Chemistry. Extraction of americium and lanthanides from nitric acid with solutions of diphenyl- and dibutyl-(diethylcarbamoylmethyl) phosphine oxides (Ph2Et2-CMPO and Bu2Et2-CMPO) in dichloroethane have been investigated as a function of the concentrations of the extractants and nitric acid (110, 111). The observed dependences are characterized... 

Mathur, J.N., Nash, K.L. 1998. Thermodynamics of extraction of Am(III) and Eu(III) from nitrate and thiocyanate media with octy l(pheny I J-YY-ditvobuty lcarbainoy I methyl phosphine oxide. Solvent Extraction and Ion Exchange 16(6) 1341-1356. 

Mathur, J.N., Murali, M.S., Ruikar, B., Nagar, M.S., Sipahimalani, A.T., Bauri, A.K., Baneiji, A. 1998. Degradation, cleanup, and reusability of octyl phcnyl-N,N -diisobutylcarbamoyl methyl phosphine oxide (CMPO) during partitioning of minor actinides from high level waste (HLW) solution. Sep. Sci. Technol. 33(14) 2179-2196. 

Several chemical techniques have also been developed, such as simple oxidation using hydrogen peroxide or lead tetraacetate.77 Both these protocols suffer from harsh reaction conditions and additional toxicity issues. A more functional group-tolerant method is the use of tris(hydroxy-methyl)phosphine to coordinate the ruthenium.78 This complex is water soluble and can be washed from the product by several simple water washes. The main drawback to this method is the large excess of phosphine needed (25 mole equiv./mole of Ru).46... 

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