Triphenylphosphine dichloride

Jean-Robert Dormoy Bertrand Castro SANOFI Chimie, Gentilly, France 

Alternate Names dichlorotriphenylphosphorane triphenyl-dichlorophosphorane chlorotriphenylphosphonium chloride. Physical Data adduct white crystalline solid mp 85-100 °C fp 20 °C. PhyP mp 80.5 °C bp 377 °C (in inert gas) df 1.194gmL- 1.6358. CI2 mp -101 °C bp -34.6°C cP 

Solubility adduct slightly sol ether, THF, PhMe sol CCI4, CH2CI2, DMF, MeCN, pyridine insol petroleum ether. Ph3P sol ether, PhH, CHCI3, AcOH less sol alcohol pract insol H2O. CI2 sol CCI4, alcohol. 

Alkyl Chlorides from Alcohols and Ethers. The reaction of Ph3PCl2 with alcohols provides an excellent synthetic method for the preparation of alkyl chlorides. Mechanistic studies suggest the rapid initial formation of an alkyloxyphosphonium intermediate which then undergoes slow conversion into Ph3PO and alkyl chloride (eq 1). It is assumed that chlorination takes place by an Sn2 reaction in most cases thus, inversion of configuration is observed in the transformation of (—)-menthol to (+)-neomenthyl chloride (eq 2). As illustrated in eq 1, primary, secondary, and even tertiary alcohols are chlorinated with PhsPCb, although reactions of tertiary alcohols are often accompanied by elimination (10%). 

Aryl Chlorides from Phenols and Arenes. Heating phenols with Ph3PCl2 at 120-140°C leads to the corresponding aryl ehlo-rides in good yield (eq 6). A related chlorination reaction employs the Ph3PCl2/BSPO Bis(trimethylsilyl) Peroxide) reagent 

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Qindamycin, 7(5)-7-chloro-7-deoxyliQcomycin [18323-44-9] (1, R = H, R = Q), also known as Cleocin, first resulted from the reaction of lincomycin and thionyl chloride (54) improved synthetic methods involve the reaction of lincomycin and triphenylphosphine dichloride or triphenylphosphine in carbon tetrachloride (55). Clindamycin is significantly more active than lincomycin against gram-positive bacteria in vitro, and is absorbed rapidly following oral adnainistration. Clindamycin 2-palmitate [36688-78-5], (6, R = R = OC(CH2) 4CH2), 2-palmitate ester of clindamycin, is... 

Within the wide range of phosphorus compounds described as activating agents for polyesterification reactions,2,310 triphenylphosphine dichloride and diphenylchlorophosphate (DPCP) were found to be the most effective and convenient ones. In pyridine solution, DPCP forms a A-phosphonium salt which reacts with the carboxylic acid giving the activated acyloxy A -phosphonium salt. A favorable effect of LiBr on reaction rate and molar masses has been reported and assumed to originate from the formation of a complex with the A-phosphonium salt. This decreases the electron density of the phosphorus atom... 

Similarly, triphenylphosphine dichloride (TPPCI2) can activate aromatic carboxylic acids in pyridine through the formation of acyloxyphosphonium salts (Scheme 2.30).313 A side reaction between tire intermediate acyloxyphosphonium species and a second carboxyl endgroup leading to the formation of anhydrides has been reported.313 This chain-limiting reaction decreases tire molar mass, while the presence of anhydride linkages in tire chains adversely affects the thermal and hydrolytic stability of the final polyester. 

Likewise, pyridines such as methyl isonicotinate 1999 or quinolines are readily oxidized by BTSP 1949 in the presence of HOReOs in CH2CI2 to give, after 6 h at 24°C, 98% yield of, e.g., methyl isonicotinate N-oxide 2000 [174] (Scheme 12.49). The oxidation of diphenylsulfide with BTSP 1949 and triphenylphosphine dichloride in acetonitrile results, after 60 h at room temperature, in only 12% diphenyl sulfoxide 2001 and 88% recovered diphenyl sulfide [175] (Scheme 12.49), whereas thianthrene 5-oxide 2002 is oxidized by the peroxy-Mo complex 2003 to give 58% of a mixture of 2004 to 2007 in which the trans 5,10-thioxide 2005 predominates [176] (Scheme 12.50). 

Triphenylphosphine dichloride exhibits similar reactivity and can be used to prepare chlorides.18 The most convenient methods for converting alcohols to chlorides are based on in situ generation of chlorophosphonium ions19 by reaction of triphenylphosphine with various chlorine compounds such as carbon tetrachloride20 or hexachloroacetone.21 These reactions involve formation of chlorophosphonium ions. 

The action of triphenylphosphine dichloride, generated from triphenylphosphine and hexachloroethane, on tertiary amines leads to phosphonium salts. Triethylamine is converted into 351 and ethyldiisopropylamine gives a mixture of the salts 352 and 353391. 

Postsynthetic intramolecular alkylation of a cysteine thiol group with a bromo amino acid has also been proposed/431 but this approach is limited by the low coupling efficiency of the bromo amino acid in the peptide synthesis due to a competing intramolecular cyclization reaction. A promising new approach consists of using suitably protected cysteine and homoserine derivatives for the peptide synthesis, whereby the side-chain hydroxy group of homoserine is protected as the TBDMS derivative which is converted on resin into the chloro derivative with freshly prepared triphenylphosphine dichloride. Upon cleavage from the resin, cyclization is performed in solution as shown in Scheme 11144]... 

Triphenylphosphine dichloride was used as a mild halogenating reagent to transform the sodium sulfonate salt 175 into the corresponding sulfonyl chloride. Further treatment using triethylamine gave the / -sultam 77 in satisfactory yield (Equation 15) <1998S423>. 

AnoAer procedure which was thought to pass through a mixed phosphoms anhydride was the acylation of Grignard reagents with an adduct formed between lithium carboxylates and triphenylphosphine dichloride (Scheme 26). The betaine (70) was the proposed tetrahedral intermediate however, since no evidence is provided, the reaction may have also proceeded by way of the acid chloride. Surprisingly, good yields of ketone are preserved even in the presence of excess nucleophile and no tertiary alcohol formation was observed. Triethylamine can be used for prior deprotonation of the carboxylic acid how-... 

Benzaldehyde reacts with triphenylphosphine dichloride to give benzal chloride in 59% yield, but cyclohexanone gives 1-chlorocyclohexene-l in 45% yield. Benzoic acid affords benzoyl chloride in 63% yield. 

Chlorination (-Butyl hypochlorite. N-Chiorosuccinimide. Cupric chloride. Dibenzoyl peroxide. Dimethylformamide. Phosphorus pentachloride. Phosphorus trichloride. Selenium oxychloride. Sodium chlorate. Sulfuryl chloride. Tetra- -butylammonium iodotetrachloride. N,2,4,6-Tetrachloroacetanilide. Thionyl chloride. Trichloromethanesulfonyl chloride. Triphenylphosphine dichloride. 

Perchloro-3-pentanone (1) is dehalogenated to perchlorodivinyl ketone (2) by triphenylphosphine.281 The triphenylphosphine dichloride formed is advantageously... 

Tris-[triphenylphosphin]- -dichlorid aus Ruthenium/lII)-chlorid-Trihydrat,... 

These reagents can be used in the same way as triphenylphosphine dichloride (equations 1-V). Each reaction leads to the polymer-bound corresponding... 

Triphenylphosphine dichloride reportedly gave a magnesium salt complex when treated with phenyl Grignard reagent (68). Decomposition of the complex occurred with alcohols and supposedly gave pentasubstituted phosphorus compounds (68), but the work could not be repeated (17,18). Blount presented convincing data that the reaction led to a phosphonium salt. 

Obviously, the triphenylphosphine dichloride obtained by Kolitowska cannot be the precursor of pentaphenylphosphorus. Equimolar quantities of phenyllithium and tetraphenylphosphonium iodide provided 22 jmder mild conditions in ether (199)... 

T riphenylphosphine—Diethyl azodi-carboxylate, 280, 645 Triphenylphosphine dibiomide, 645-646 Triphenylphosphine dichloride, 646-647 Triphenylphosphine dihaiides, 647-648 Triphenylphosphine diiodide, 648 Triphenylphosphine ditriflate, 648 Triphenylphosphite methiodide, 649 Triphenyl phosphite ozonide, 435 Triphenyl(prop-2-ynyl)phosphonium bromide, 494 Triphenylsilanol, 655, 656 Triphenylstannane, 649 Triphenyltin hydride, 649 Triphenylvinylsilane, 637 Triphosphopyridine nucleotide, 36-37 Tri- -propyl orthovanadate, 655 Tris-annelation, 410 Ttis(aquo)hexa-fi-acetato-p,-oxotri-ruthenium acetate, 425-426,650 Tris(dimethoxyboryl)methane, 328, 329 Tris(dimethylamino)borane, 554 Trishomocubanone, 108 Tris(neomenthyldiphenylphosphine)-chlororhodium, 416... 

The reaction of perchlorotoluene with triphenylphosphine has been studied (Diaz-Alzamora, 1968). It is noted that the reaction with carbon tetrachloride gives a mixture of (dichloromethylene)triphenylphosphorane and triphenylphosphine dichloride (Appel et al., 1976 Burn and Cadogan, 1963 Rabinowitz and Marcus, 1962). (The resulting reaction mixture was usually treated with water.) The sequence (49), involving a nucleophilic attack on chlorine, has been proposed. 

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