Carbonylation of allylic chlorides

The 3.7-octadienoate 399 is obtained by the carbonylation of allyl chloride and butadiene[255]. 

PdCl2(tppts)2 exhibited high catalytic activity (TOF=1860 h-1) for the carbonylation of allyl chloride to the desired product p,y-butenoic acid [Equation (8)] at 40°C and atmospheric CO pressure in an aqueous(NaOH)/toluene two phase system471 By-products were a,P-butenoic acid and allyl alcohol. The yield of butenoic acids was 94% with a 3,y/a, 3 ratio of 21 471... 

The carbonylation of allyl chloride with a nickel carbonyl catalyst appears to be the first useful example of an organic halide reaction to be reported (6). In alcohol solution at 50 atm pressure and 100°, mixtures of esters of 2- and 3-butenoic acid were obtained in about 50% yield with the 3-isomer predominating. Such high pressures and temperatures are probably not necessary for this reaction, however (7) ... 

Bis(triphenylphosphine)palladium dichloride [(Ph3P)2PdCl2] can also be used as a catalyst for the phase-transfer carbonylation of halides. However, considerably more drastic conditions [95°C, 5 atm] are required when compared with Co2(CO)8 (44). The carbonylation of allyl chlorides can be catalyzed by nickel tetracarbonyl, giving isomeric mixtures of bu-tenoic acids. There is evidence for the intermediacy of polynuclear nickel-ates in this phase-transfer process (45). Acetylene insertion did not occur... 

Ru(II), Ru(I) and Ir(I) in an aqueous medium (90). Data for the different complexes are shown in Table II. The highest conversion is observed with the ruthenium(II) complexes, which correlates with the facility of Ru complexes to catalyze other hydrogen transfer reactions. The complex PdCl2(TPPMS)2 has been used as a two-phase aqueous-organic catalyst for the carbonylation of allylic chlorides (Eq. 30) 91). The reaction pro-... 

The catalytic carbonylation of allyl chloride to form 3-butenoate proceeds through a 7r-allyl complex which is formed by the oxidative addition of allyl chloride to metallic palladium. The 7r-allyl complex formation has been reported by Fischer and Burger (4) with allyl bromide and palladium as a supporting evidence. The carbonylation then proceeds by the insertion of carbon monoxide as before. 

In general for carbonylations, palladium as catalyst metal is preferable to nickel with respect of catalyst efficiency. Thus, Okano, Kiji, and co-workers described some other efficient palladium-catalyzed carbonylations of allyl chloride and substituted allyl halides (Eqs. 5-10). In greater detail, the water-soluble palladium complex PdCl2[Ph2P(w-C6H4S03Na)]2 has been used in a two-phase system (e.g., aqueous NaOH/benzene medium) at atmospheric carbon monoxide pressure, giving 3-butenoic acids [20], In the carbonylation of allyl chloride a mixture of 2-bute-noic acid, which was formed by base-catalyzed isomerization, and 3-butenoic acid was obtained in up to 90% yield (TON = 135), albeit at moderate selectivity (24 76). Clearly, the isomerization depends on the concentration of the base and was therefore suppressed by a method of continuous addition to the aqueous medium. 

Fig. 33. Carbonylation of allyl chloride in the presence of heterogeneous (1) and homogeneous (2) catalysts homogeneous catalyst - [Pd(NH3)4] [ -CH2CgH4S03]2, heterogeneous catalyst - [Pd(NH3)4] supported on polystyrenesulfoacid [212]...

In general, for carbonylations, Pd is preferable to Ni as the catalyst metal with respect of catalyst efficiency. Thus Okano et al. [10] described some other efficient Pd-catalyzed carbonylations of allyl chloride and substituted allylic halides (e.g.. Scheme 4). 

Unsaturated esters are prepared by the carbonylation of allylic compounds under various conditions depending on the leaving groups. Carbonylation of allylic chlorides proceeds under two-phase (liquid-solid) and mild conditions (room temperature, 1 atm of CO in the presence of K2CO3 in EtOH) using ligandless Pd catalyst. Ethyl 4-phenyl-3-butenoate was obtained from cinnamyl chloride in 94% yield [143]. Allylic carbonates are reactive and their carbonylation proceeds under mild neutral conditions [144]. 

In the presence of main group organometallic compounds, ketones are obtained. Carbonylation of allylic ester 382 with alkylzinc reagent afforded the ketone 383 in high yield [149]. Carbonylation of allyl chloride 384 in the presence of tin hydride afforded the -unsaturated aldehyde 385 via hydrogenolysis of acylpalladium intermediate [150]. 

Carbonylation of allyl bromides and chlorides has been achieved in presence of a nickel catalyst in aqueous NaOH at atmospheric pressure. Subsequently it is found that Palladium-catalysed carbonylation of allyl chloride proceeded smoothly in two-phase aqueous NaOH/benzene under atmospheric pressure at room temperature (Scheme 143). " ... 

General.—catalyst system for the production of linear acids or esters by carbonylation of terminal olefins has been described excellent yields and a high degree of linearity enhance the utility of this system. A related process concerning the carbonylation-dimerization of butadiene is noted a palladium acetonylacetonate-triphenylphosphine complex is catalytically active for the preparation of ethyl nona-3,8-dienoate from butadiene, carbon monoxide, and ethanol. The preparation of but-3-enylsuccinic acid by the catalysed carbonylation of allyl chlorides with double-bond insertion is reported the intermediacy of but-3-enoic acid is suggested. ... 

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