From Metallated Phosphines

From Metallated Phosphines.—Lithium diphenylphosphide and ethylene oxide produce (7), which when added to chlorodibutyl- or chlorodiphenyl-phosphine yields 2-diphenylphosphinoethyl phosphinites (8). 

8-Quinolylphosphines have been prepared from the reaction of 8-chloroquinoline and potassium diphenylphosphide, or the quinolyl-lithium derivative and a chlorophosphine.  

A phenyl group can be cleaved, with lithium, from alkylphenylphos-phines to give lithium alkylphenylphosphides, which with diphenylvinyl- 

The ditertiary phosphines (11), prepared from the corresponding alkyl chloride and lithium diphenylphosphide (10), - react with sodium in liquid ammonia to give the phosphines (12). 

Phosphides add to the double bond of j8-unsaturated carbonyl compounds to give the phosphines (13). 

From Metallated Phosphines. The reactions of organophosphide anions with alkyl tosylates have been used to prepare the chiral diphosphines (12) and (13), and also a range of phosphines bearing chiral substituents derived from various natural products.  

The reaction of lithium diphenylphosphide with a bis-ben2ylic halide has been employed in the synthesis of the diphosphine (14), which is of interest as a trans-spanning ligand. Displacement of halide ion from a vinylic carbon atom occurs in the reaction of cis- and fm/zi -iS-ctilorovinyldiphenylarsines with lithium diphenylphosphide, which proceeds stereospecifically with the formation of the corresponding cis- and rra 5-phosphine-arsines (15). Surprisingly, the reaction of lithium diphenylphosphide with a thirty-fold excess of cw-l,2-dichloroethene yields only the cis-diphosphine (16).  

BenSs and J. HetflejS, Coll. Czech. Ghent. Comm., 1976, 41, 2256, 

Further instances of the probable attack of phosphide anions on halogen have appeared. Lithium bis(trimethylsilyl)phosphide reacts with 1,2-dibromoethane to form the diphosphine (17), together with ethylene. Similarly, the reaction of 

Dimetallodiphosphide reagents of type (18) react with difunctional halogen derivatives to form five-, six-, or seven-membered heterocycles of types (19) and (20). The reagent (18 R=Ph, M=Li, =2) is conveniently prepared by the cleavage of l,2-bis(diphenylphosphino)ethane, using lithium.  

From Metallated Phosphines. The preparations of a number of flexible aliphatic ligands, e.g. (6), containing the dimethylphosphino-group have been described, in which the sodium dimethylphosphide used was prepared from tetramethyldiphosphine,  

The chiral phosphines (7) and (8) have been obtained by the reaction of sodium diphenylphosphide with menthyl chloride and neomenthyl chloride, respectively.  

Michael addition of sodium phosphides to alkenes containing nitro- or sulphonyl-groups gave the expected (2-nitroalkyl)- and (2-suIphonylalkyI)-phosphines.  

The reaction of potassium phenyl(trimethylsilyl)phosphine with bromine or iodine in benzene gave pentaphenylpentaphospholan and the phosphine (11). This phosphine can also be obtained from dipotassium phenylphosphide, prepared by ring cleavage of pentaphenylpentaphospholan with potassium, and trimethylchlorosilane.  

The phosphane (12) is ring-expanded by metallation and subsequent reaction with dichloromethane.  

From Metallated Phosphines.— The polymeric ligand (4) has been formed from chloromethylated styrene-divinylbenzene copolymer and lithium diphenylphosphide. Trimethylsilylation of potassium phenyl-phosphide gave the phosphine (5), which on treatment with bromine gave phenylphosphorus. (Trimethylstannyl)phosphine (6) has been prepared in high yield from trimethyltin chloride and lithium tetraphosphinoaluminate.  

Suoboda, M. Cerny, and J. Hetflejs, Tetrahedron Letters, 1971, 4787. 

The elusive tricarbethoxyphosphine (7) has been obtained from the reaction of trisodium phosphide and ethyl chloroformate.  

Ethylphosphorus reacts with various amounts of phenyl-lithium to give the lithium phosphides (8), which are more reactive than ethylphosphorus towards phenyl-lithium and can react further to give complex mixtures of other lithium phosphides. Unsaturated phosphines (9) have been prepared with high stereospecificity by the addition of di-t-butylphosphine to 

Further examples of chiral diphosphines in the DIOP- and 2,4-disubstituted pyrrolidine- series have also been 

A study of the generation of diarylphosphide reagents by the alkali metal-induced cleavage of triarylphosphines bearing electron-donating groups has revealed a rather confusing picture. 

Compounds.- A third part of a review of P-H addition to unsaturated systems has appeared, covering addition to unsaturated ligands in the coordination sphere of a metal.Addition of diphenylphosphine to the free vinyl group of the [4+2]cycloadduct of 3,4-dimethyl-l-phenylphosphole and phenyldivinylphosphine (both in the form of metal complexes) has led to the unsymmetrical triphosphine (40), isolated as the related metal complex.A similar u.v.-induced addition to methyl(vinyl)cyclotetrasiloxane has given a tetraphosphine which, on treatment with acid, forms an 

Free radical-induced additions have been used in the synthesis of a range of phosphines bearing other nucleophilic groups, e.g., (41), useful for specific peptide bond cleavage of proteins.A further example of the formation of the phosphorinanone system by addition of phenylphosphine to a divinyl ketone derivative has been described.Two reports have appeared of the addition of secondary phosphines to maleic anhydride and related activated olefins, to give functionalised tertiary phosphines, e.g., (42). A route to allylphosphines is provided by base- 

Preparation of Phosphines from Metallated Phosphines. This route has continued to find extensive application for the preparation of a wide range of new phosphines. The reaction of lithium diarylphosphides with tosylate esters has been employed in the synthesis of the chiral phosphines (19) and (20) . In the preparation of fully alkylated chiral diphosphines in the DIOP series (21), the reactions of lithium dialkylphosphides with ditosylate precursors surprisingly give intractable products. Similar problems are encountered in the related reactions of chloromethyl, bromomethyl, and iodomethyl precursors, the main 

Interest continues in the use of reagents obtained by lithiation at carbon adjacent to phosphorus. The reaction of lithiomethyldiphenylphosphine with chlorosilanes has given the phosphines (25). Full details have now appeared of studies of lithiation at carbon of methylphosphines co-ordinated to nickel.  

Yamagata, and S. Otsuka, Chem. Lett., 1982, 265. 

Many applications of sodium and potassium organophosphides have been reported in the past year. The reaction of sodium diphenylphosphide with tosylates has been employed in the synthesis of steroidal phosphines. This reagent has also been used in the synthesis of a range of carbohydrate-derived phosphines, and in the synthesis of the phosphine (26), which can be linked to a silica support by treatment with acid. The reaction of sodium diphenylphosphide with o-difluorobenzene affords a convenient, one-pot synthesis of o-bis(diphenyl-phosphino)benzene. Sodium dimethylphosphide has been used to convert 

Baudler s group (and others) continue to make extensive use of alkali-metal polyphosphide reagents in the synthesis of both cyclic and acyclic polyphosphines. A wide range of new systems has been described in the past year, and the field as a whole has been reviewed.  

2 Preparation of Phosphines from Metallated Phosphines.- It has been shown that phosphide anions may be generated from primary and secondary phosphines under aqueous conditions using concentrated aqueous alkali in DMSO or other dipolar aprotic solvents. 

Alkylation of the resulting anions has given a range of secondary 

P7Bu 5, (23), has been isolated from the reaction of butyldi- 

Sodium and potassium organophosphide reagents continue to be employed in the synthesis of new phosphines. The tetradentate 

L-cysteine, L-methionine, and D-penicillamine, have been prepared 

---

Preparation of Phosphines from Metallated Phosphines. - The first soluble crystalline potassium salt (36) of a primary phosphine has been prepared, and its... 

Preparation of Phosphines from Metallated Phosphines. Metallophosphide reagents continue to find extensive use in the synthesis of new phosphines and, as... 

Preparation of Phosphines from Metallated Phosphines.- The generation of arylphosphide reagents by the reductive cleavage of carbon-phosphorus bonds using alkali metals has received detailed study for a wide range of functionalised triarylphosphines and related... 

Preparation of Phosphines from Metallated Phosphines. - Alkali metal-free phosphide anions have been shown to be formed under synthetically useful conditions in the equilibria between primary or secondary phosphines with the Schwesinger bases (23). Techniques have been developed for the preparation of alkali metal diphenylphosphide reagents in high purity, as evidenced by P nmr studies. The same paper reports a study of the course of the reactions between potassium diphenylphosphide and a series of aryl-, n-alkyl- and neopentyl-halides. The results provide the first evidence of the involvement of single electron transfer (SET) processes in the reactions of alkyl halides. This pathway is dominant in the case of neopentyl-type iodides, but plays only a minor role in the related reactions of neopentyl-type bromides and chlorides. No evidence was adduced of the involvement of SET processes in the reactions of unhindered... 

OXYGEN ATOM TRANSFER FROM METAL PHOSPHINE HYDROPEROXIDES AND SUPEROXIDES... 

---