Amine oxides phosphines

Amino acids Amino acids, amines, phosphine, oxide, alkaloids based 108-118... 

Conversion of aliphatic and aromatic amine N-oxides to corresponding amines, phosphine oxides to phosphines and triaryl arsine oxides to triaryl arsines have also been achieved. These reactions require the presence of HMPA as cosolvent (Zhang and Lin, 1987). 

In general, peroxomonosulfates have fewer uses in organic chemistry than peroxodisulfates. However, the triple salt is used for oxidizing ketones (qv) to dioxiranes (7) (71,72), which in turn are useful oxidants in organic chemistry. Acetone in water is oxidized by triple salt to dimethyldioxirane, which in turn oxidizes alkenes to epoxides, polycycHc aromatic hydrocarbons to oxides and diones, amines to nitro compounds, sulfides to sulfoxides, phosphines to phosphine oxides, and alkanes to alcohols or carbonyl compounds. 

Tertiary phosphine oxides are stable. The temperatures required for thermal decomposition are approximately 300°C higher than the corresponding amine oxides (96). Trimethyl phosphine oxide is stable to 700°C. 

Although unsynunetrically substituted amines are chiral, the configuration is not stable because of rapid inversion at nitrogen. The activation energy for pyramidal inversion at phosphorus is much higher than at nitrogen, and many optically active phosphines have been prepared. The barrier to inversion is usually in the range of 30-3S kcal/mol so that enantiomerically pure phosphines are stable at room temperature but racemize by inversion at elevated tempeiatuies. Asymmetrically substituted tetracoordinate phosphorus compounds such as phosphonium salts and phosphine oxides are also chiral. Scheme 2.1 includes some examples of chiral phosphorus compounds. 

Tlie isolable dithiiranes (4 and 7) are fairly stable under acidic conditions but quickly lose a sulfur atom to give the corresponding thioketones under basic conditions (97BCJ509). Tliey are quite sensitive toward amines and phosphines. Oxidation with MCPBA gave the corresponding dithiirane 1-oxides in high yields. 

In the course of this study, the authors determined /Lvalues for dibenzyl, methyl phenyl, methyl p-nitrophenyl, di-p-tolyl, di-isopropyl and tetramethylene sulphoxides and for diethyl, dipropyl and dibutyl sulphites. The /Lscales are applied to the various reactions or the spectral measurements. The /Lscales have been divided into either family-dependent (FD) types, which means two or more compounds can share the same /Lscale, family-independent (FI) types. Consequently, a variety of /Lscales are now available for various families of the bases, including 29 aldehydes and ketones, 17 carboxylic amides and ureas, 14 carboxylic acids esters, 4 acyl halides, 5 nitriles, 10 ethers, 16 phosphine oxides, 12 sulphinyl compounds, 15 pyridines and pyrimidines, 16 sp3 hybridized amines and 10 alcohols. The enthalpies of formation of the hydrogen bond of 4-fluorophenol with both sulphoxides and phosphine oxides and related derivatives fit the empirical equation 18, where the standard deviation is y = 0.983. Several averaged scales are shown in Table 1588. 

A few functional dihalides have been prepared. Some of these monomers are tabulated in Table 6.2. The monomers could be nitrated and then reduced to amine-functionalized monomers (Scheme 6.26).203 This approach was used to nitrate DCDPS or bis-4-fluorophenyl phenyl phosphine oxide.204 These monomers were used to copolymerize with some other activated dihalides as the comonomers. 

D. Miscellaneous.—A further study of the reactions of diphenyl-phosphine oxide with tetracyclone has confirmed that the reaction yields the oxide (30) under mild, basic conditions, and that the reaction is thermally reversible. The displacement of halogen from phosphorus by amino-compounds has been used in the synthesis of a number of aminofluoro-phosphine oxides (31), and of A-methyl-AA-bis(dichlorophosphinyl)-amine (32). ... 

C. Reactions not involving P=0 or P=S Groups.—Enamine phosphine oxides (45) have been prepared by the addition of amines to 1-alkynyl-phosphine oxides, and the reactions of their anions with various electrophiles have been reported. - With ketones a Wittig-type reaction leads to the formation of a/3-unsaturated ketones, in 53—70% yield, while with epoxides cyclopropyl ketimines are formed. A Diels-Alder reaction of l-phenyl-A -phospholen-l-oxide (46) with 1,4-diacetoxybutadiene has been used in the preparation of l-phenyl-benzo[/>]phosphole (47), as... 

Polymeric or monomeric complexes are formed in the reaction between zinc halides and dimethyl(aminomethyl)phosphine oxide dependent on the ratio of reactants. The ligand can bind as bidentate to one metal center or bridge two metal centers through the amine N and phosphine oxide O atoms.851... 

The reaction of alcohols with CO was catalyzed by Pd compounds, iodides and/or bromides, and amides (or thioamides). Thus, MeOH was carbonylated in the presence of Pd acetate, NiCl2, tV-methylpyrrolidone, Mel, and Lil to give HOAc. AcOH is prepared by the reaction of MeOH with CO in the presence of a catalyst system comprising a Pd compound, an ionic Br or I compound other than HBr or HI, a sulfone or sulfoxide, and, in some cases, a Ni compound and a phosphine oxide or a phosphinic acid.60 Palladium(II) salts catalyze the carbonylation of methyl iodide in methanol to methyl acetate in the presence of an excess of iodide, even without amine or phosphine co-ligands platinum(II) salts are less effective.61 A novel Pd11 complex (13) is a highly efficient catalyst for the carbonylation of organic alcohols and alkenes to carboxylic acids/esters.62... 

Figure 17.17 The Staudinger reaction involves the reduction of an azide to a primary amine with loss of N2 and the concomitant oxidation of a phosphine derivative to a phosphine oxide.

The reactions used for synthesis of II-VI (CdSe, CdTe), III-V (InP, InAs), and IV-VI (PbS, PbSe, PbTe) semiconductor nanocrystals are outlined by Schemes 3-5.4,17,30-32 The syntheses are carried out at high temperatures, and in the presence of long-chain alkylphosphines (trioctylphosphine,TOP), alkyl-phosphine oxides (trioctylphosphine oxide, TOPO), alkylamines (hexadecyl-amine, HD A), and alkylphosphonic acids as the stabilizing agents. 

The electrooxidation of organosilicon compounds containing heteroatoms has been investigated extensively and various synthetic applications have been developed. Cooper and Owen studied the oxidation potentials of a series of silyl-substituted amines, phosphines, and sulfides, and observed that silyl substitution at the carbon adjacent to the heteroatom caused a significant decrease in the oxidation potentials (Table 4) [35]. 

A synthesis of novel chiral phosphine oxide aminal 113 has been developed by reacting phosphine oxide aldehyde 111 with diamine 112. The condensation gave a single diastereomer of the phosphine oxide aminal in 65% yield. This compound can be used as chiral auxiliary in asymmetric synthesis (Equation 15) <1996TA3431, 1996TL3051, 1996TL7465>. 

Tertiary amine polymethacrylates, 20 471 tertiary-butyldimethylsilyl (TBDMS), cleavage of, 16 559, 560 Tertiary creep, 13 472 Tertiary diperoxyketals, 18 457 Tertiary metal phosphates, 18 840 Tertiary nitriles, 12 180 Tertiary phosphine oxides, 19 66 Tertiary phosphines, 19 64 Tertiary recycling, 21 449 of PET, 21 450... 

Primary amines react with benzylbis(a-hydroxybenzyl)phosphine oxide (39) to give a-aminoalkylphosphine oxides (40) and (41 ),34 and the reaction has been... 

The secondary phosphine oxide (104) has been reported as an intermediate in the reaction of benzylbis(a-hydroxybenzyl)phosphine oxide (103) with amines to give (105).79 The same authors now report the results of direct reaction of (103) with imines80 to give (105) and the reaction of (103) with aldehydes81 to give acetals (106). 

A synthesis of A-substituted a-aminobenzylphosphinic acids starts from ammonium hypophosphite this is allowed to react with primary amines together with aldehydes or ketones in the presence of HC1.60 The nature of the products and general success of the Atherton-Todd reaction for the preparation of dialkyl- and diaryl-phosphinic amides from secondary phosphine oxides depends on the order in which reactants are mixed and on the choice of polyhalogen reactant.61... 

Like its monomeric counterpart, the polymeric reagent is inert to simple amines, amides, alcohols and phenols, but easily oxidizes thiols to disulphides, phosphines to phosphine oxides, hydroquinone and catechol to quinones, and thioketones, thioesters and trithiocar-bonates to the corresponding 0x0 derivatives, in dichloromethane, chloroform or acetic... 

---