Phosphines primary

Phosphine, primary and secondary phosphines react with Grignard reagents as active hydrogen compounds 214-216,493)... 

One of the most reactive, with respect to phosphine, ketones, hexafluoro-cyclobutanone, produces with phosphine primary and secondary 1 hydroxy-fluorocyclobutylphosphines instead of phosphine oxides ... 

Tertiary phosphines Secondary phosphines Primary phosphines Tertiary amines Secondary amines Primary amines... 

Buchwald s XPhos ligand (L7) works well to catalyze the amination of 5-bromopyrimidine with anilines and secondary cyclic amines.67 Buchwald also found that ligands L20 and L21 were the best ligand for the palladium-catalyzed amination of benzothiazoles with secondary amines and anilines. Hartwig reports that (r-Bu)3P was excellent for the catalytic amination of 2-chloroheteroaryl compounds with secondary amines and anilines.35,68 As with other examples using bulky mono-dentate phosphines, primary aliphatic amines were not reported. 

The reaction with sodium sulfite or bisulfite (5,11) to yield sodium-P-sulfopropionamide [19298-89-6] (C3H7N04S-Na) is very useful since it can be used as a scavenger for acrylamide monomer. The reaction proceeds very rapidly even at room temperature, and the product has low toxicity. Reactions with phosphines and phosphine oxides have been studied (12), and the products are potentially useful because of thek fire retardant properties. Reactions with sulfide and dithiocarbamates proceed readily but have no appHcations (5). However, the reaction with mercaptide ions has been used for analytical purposes (13)). Water reacts with the amide group (5) to form hydrolysis products, and other hydroxy compounds, such as alcohols and phenols, react readily to form ether compounds. Primary aUphatic alcohols are the most reactive and the reactions are compHcated by partial hydrolysis of the amide groups by any water present. 

Toxicity. Lethality is the primary ha2ard of phosphine exposure. Phosphine may be fatal if inhaled, swallowed, or absorbed through skin. AH phosphine-related effects seen at sublethal inhalation exposure concentrations are relatively small and completely reversible. The symptoms of sublethal phosphine inhalation exposure include headache, weakness, fatigue, di22iness, and tightness of the chest. Convulsions may be observed prior to death in response to high levels of phosphine inhalation. Some data are given in Table 2. 

In the case of olefins, the reaction generally yields a mixture of primary, secondary, and tertiary phosphines, as follows ... 

In contrast, if the olefin is more stericaHy hindered (branched) and/or the reaction is operated at a higher pressure (4 MPa), formation of the primary and secondary phosphines is favored as in the reaction with 2,4,4-trim ethyl -1 -pen ten e [107-39-1]. 

The mixture can be separated by distillation. The primary phosphine is recycled for use ia the subsequent autoclave batch, the secondary phosphine is further derivatized to the corresponding phosphinic acid which is widely employed ia the iadustry for the separation of cobalt from nickel by solvent extraction. With even more hindered olefins, such as cyclohexene [110-83-8] the formation of tertiary phosphines is almost nondetectable. 

In the presence of a large excess of PH, primary phosphines, RPH2, are formed predominantiy. Secondary phosphines, R2PH, must be either isolated from mixtures with primary and tertiary products or made in special multistep procedures. Certain secondary phosphines can be produced if steric factors preclude conversion to a tertiary product. Both primary and secondary phosphines can be substituted with olefins. After the proper selection of substituents, mixed phosphines of the type RRTH or RR R T can be made. 

In general, if the desired carbon—phosphoms skeleton is available in an oxidi2ed form, reduction with lithium aluminum hydride is a powerful technique for the production of primary and secondary phosphines. The method is appHcable to halophosphines, phosphonic and phosphinic acids as well as thein esters, and acid chlorides. Tertiary and secondary phosphine oxides can be reduced to the phosphines. 

The addition of alkyl haUdes to phosphines is analogous to the reactions with amines. Because primary phosphonium salts are highly dissociated, the reaction proceeds to the tertiary or quartemary salts. 

Metal phosphides can be employed to direct the action of alkyl hahdes more toward primary and secondary phosphines. 

The addition of P—H bonds across a carbonyl function leads to the formation of a-hydroxy-substituted phosphines. The reaction is acid-cataly2ed and appears to be quite general with complete reaction of each P—H bond if linear aUphatic aldehydes are used. Steric considerations may limit the product to primary or secondary phosphines. In the case of formaldehyde, the quaternary phosphonium salt [124-64-1] is obtained. 

Secondary phosphines are likewise intermediates in the syntheses of phosphonites. The primary and secondary phosphines can also be used to make other mixed phosphines. 

Primary and secondary phosphines can be treated with halogenating agents to produce halophosphines. 

Tertiary phosphines and primary and secondary phosphines can be oxidized by elemental halogen to halophosphine halides. 

Because of their relative instabiUty, primary phosphine oxides caimot be isolated and must be converted direcdy to derivatives. Primary and secondary phosphine oxides undergo reactions characteristic of the presence of P—H bonds, eg, the base-cataly2ed nucleophilic addition to unsaturated compounds such as olefins, ketones, and isocyanates (95). 

This primary aminoborane is a useful reagent for attaching B—N moieties to other elements, eg, (borylarnino)phosphines, or for extending short B—N chains, eg, diborylamines. 

Primary Amyl Alcohols. Primary amyl alcohols (qv) are manufactured by hydroformylation of mixed butenes, followed by dehydrogenation (114). Both 1-butene and 2-butene yield the same product though in slightly different ratios depending on the catalyst and conditions. Some catalyst and conditions produce the alcohols in a single step. By modifying the catalyst, typically a cobalt carbonyl, with phosphoms derivatives, such as tri( -butyl)phosphine, the linear alcohol can be the principal product from 1-butene. 

Although the synthetic approaches taken by these two groups appear more or less straightforward, there are two difficulties associated with the synthesis of these phosphorus maeroeyeles which make these preparations all the more substantial. The first of these problems is the air sensitivity of phosphines, especially primary and secondary... 

Codeposition of silver vapor with perfluoroalkyl iodides at -196 °C provides an alternative route to nonsolvated primary perfluoroalkylsilvers [272] Phosphine complexes of trifluaromethylsilver are formed from the reaction of trimethyl-phosphme, silver acetate, and bis(trifluoromethyl)cadmium glyme [755] The per-fluoroalkylsilver compounds react with halogens [270], carbon dioxide [274], allyl halides [270, 274], mineral acids and water [275], and nitrosyl chloride [276] to give the expected products Oxidation with dioxygen gives ketones [270] or acyl halides [270] Sulfur reacts via insertion of sulfur into the carbon-silver bond [270] (equation 188)... 

Reaction of adsorbed inhibitors In some cases, the adsorbed corrosion inhibitor may react, usually by electro-chemical reduction, to form a product which may also be inhibitive. Inhibition due to the added substance has been termed primary inhibition and that due to the reaction product secondary inhibition " . In such cases, the inhibitive efficiency may increase or decrease with time according to whether the secondary inhibition is more or less effective than the primary inhibition. Some examples of inhibitors which react to give secondary inhibition are the following. Sulphoxides can be reduced to sulphides, which are more efficient inhibitorsQuaternary phosphonium and arsonium compounds can be reduced to the corresponding phosphine or arsine compounds, with little change in inhibitive efficiency . Acetylene compounds can undergo reduction followed by polymerisation to form a multimolecular protective film . Thioureas can be reduced to produce HS ions, which may act as stimulators of... 

Like gold, silver readily forms insoluble (yellow) thiolates [Ag(SR)] primary alkylthiolates are thought to have non-molecular structures but with bulky tertiary alkyls (n = 8), probably having a cyclic structure. Addition of excess thiolate leads to the formation of clusters like Ag6(SPh)g, Ag5(SPh)7 and Ag5(SBu )6 (phosphine adducts are known, too). 

The nucleophilic displacement reactions with azide, primary amines, thiols and carboxylatc salts arc reported to be highly efficient giving high (>95%) yields of the displacement product (Table 9.25). The latter two reactions are carried out in the presence of a base (DBU, DABCO). Radical-induced reduction with tin hydrides is quantitative. The displacement reaction with phenolates,61j phosphines,6M and potassium phthalimide608 gives elimination of HBr as a side reaction. 

Oxidation of Phosphines and Phosphine Oxides Phosphinic acids may be prepared by controlled oxidation of primary phosphines, RPH2. In most cases air, oxygen, or hydrogen peroxide is sufficient [162-164] see Eq. (95) ... 

Using other alkylated benzene hydrocarbons, e.g., amyl-, hexyl-, octyl-, or nonylbenzene, similar surface-active phosphinic acids are formed by reaction with PC13 in the presence of anhydrous aluminum trichloride. The resulting alkylarylphosphinic acids form stable salts with primary, secondary, or tertiary hydroxy amines or aromatic amines [166,171]. 

Katti KV, Pillarsetty N, Raghuraman K (2003) New Vistas in Chemistry and Applications of Primary Phosphines. 229 121-141... 

Other cyclizations at phosphorus have been observed when certain phosphinates were used in the acid-catalyzed Mannich reaction. As observed previously with various phosphonous acid derivatives, reaction of aliphatic phosphinic acids with primary amines favored the formation of 2 1 adducts (73). Thus, glycine and other a-amino acids reacted under the typical conditions with excess formaldehyde and alkyl phosphonous acids to give the bis-phosphinylmethyl adducts 125. 

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