Triethyl phosphonium chloride

Compared to what we know about amines as bases at present we have but little information on the phosphines. However, what results we do have raise a number of interesting questions and help to paint in the first guide lines to an understanding of relationships among basic atoms of groups Va and Via. Although phosphonium salts such as triethyl phosphonium chloride have been known for many years, we have only recently had any means for answering the crucial questions of how the basicities of the phosphines vary with their structures and how they compare with the amines. 

When the halogen compound employed in the first step has an activated halogen atom (RCH CHCHjX, QHjCHjX, XCH2CO2H) a simpler procedure known as the Horner phosphonate modification of the Wittig reaction is applicable. When benzyl chloride is heated with triethyl phosphite, ethyl chloride is eliminated from the initially formed phosphonium chloride with the production of diethyl benzylphosphonate. This phospho-... 

Triethyl - carboxymethyl -pho sphonium chloride, (C gHg) 3P (CH3. C02H)C1, is formed when tnethyl-carbethoxymethyl-phosphonium chloride is treated with silver oxide and the anhydride thus produced,... 

Triethyl-carbethoxymethyl-phosphonium chloride, ( 2115)3 P(CH2.C02C2H5)C1, is the condensation product of monochloracetic ester and triethylphosphine. It has only been isolated as a viscous mass. 

It is interesting to note that the very widely used Makosza catalyst , benzyl triethyl ammonium chloride, does not show high efficiency in this study. 4) Phosphonium ions are somewhat more effective and thermally stable than the corresponding ammonium catalysts and both are better than arsonium systems. 5) Substitution of the quaternary ion by alkyl rather than aryl groups yields more effective catalysts. 6) Reaction rates are generally greater in orf/io-dichlorobenzene (and presumably in other chlorocarbon media) than in benzene, and botli are better than heptane. In connection with this latter point, Ugelstad and coworkers have studied the reactions of quaternary ammonium phenoxide ions with alkyl halides in a variety of media and concluded that the... 

N-acylaziridines occurs on treatment with triphenylphosphine with the formation of the ylides (67), thereby providing a route to a-substituted primary allylic amines via their in situ reactions with aldehydes.The reactions of triphenylphosphine with epoxides in phenolic media provide a new access to the vinyl-phosphonium salts (68). A route to 1-hydroxyalkylphosphonium salts is provided by the reactions of trimethyl- or triethyl-phosphine with aldehydes or ketones in the presence of anhydrous acids. The related 1-trimethylsiloxyalkylphosphonium salts can be isolated in the presence of trimethylsilyl chloride.Further Wittig-products have been isolated from the reaction of 1,2,3-indanetrione with triphenylphosphine, and, in related work, it has been shown that furoin is deoxygenated on heating with triphenylphosphine to form 2-furfuryl(2-furyl)ketone and triphenylphosphine oxide.The structure of the blue product from the reaction of triphenylphosphine with 2,3,5,6-tetracyano-7-oxabicyclo(2,2,1]hepta-2,5-diene has now been shown by X-ray techniques to be the stable ylide (69). ... 

It is known that triethyl phosphite reacts with carbon tetrachloride to give ethyl chloride and diethyl (trichloroethyl)phosphonate. Ionic and radical mechanisms have been suggested to account for this remarkable reaction. According to the most reasonable, fundamental one (61), the reaction is initiated by a nucleophilic attack on chlorine (not an Arbusov reaction) followed by formation of the phosphonium salt [71] (Atkinson et al., 1969). 

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