Butyrolactones, carbon monoxide

With various catalysts, butanediol adds carbon monoxide to form adipic acid. Heating with acidic catalysts dehydrates butanediol to tetrahydrofuran [109-99-9] C HgO (see Euran derivatives). With dehydrogenation catalysts, such as copper chromite, butanediol forms butyrolactone (133). With certain cobalt catalysts both dehydration and dehydrogenation occur, giving 2,3-dihydrofuran (134). 

In the reaction of aHyl alcohol with carbon monoxide using cobalt carbonyl, Co(CO)g as the catalyst, in the presence of a small amount of hydrogen and carbon monoxide under pressure, 9.8 MPa (1420 psi), at 100°C, intramolecular hydroesterification takes place, yielding y-butyrolactone [96-48-0] (16). 

Pyrrohdinone (2-pyrrohdone, butyrolactam or 2-Pyrol) (27) was first reported in 1889 as a product of the dehydration of 4-aminobutanoic acid (49). The synthesis used for commercial manufacture, ie, condensation of butyrolactone with ammonia at high temperatures, was first described in 1936 (50). Other synthetic routes include carbon monoxide insertion into allylamine (51,52), hydrolytic hydrogenation of succinonitnle (53,54), and hydrogenation of ammoniacal solutions of maleic or succinic acids (55—57). Properties of 2-pyrrohdinone are Hsted in Table 2. 2-Pyrrohdinone is completely miscible with water, lower alcohols, lower ketones, ether, ethyl acetate, chloroform, and benzene. It is soluble to ca 1 wt % in aUphatic hydrocarbons. 

Carboxyiation of y-butyrolactones.1 y-Butyrolactones react with carbon monoxide in HF-SbF5, followed by an aqueous workup, to form dicarboxylic acids in quantitative yield. 

Trimethylene oxide also reacts rapidly with cobalt hydrocarbonyl and carbon monoxide at 0° C to produce 4-hydroxybutyrylcobalt tetracarbonyl, identified by means of its triphenylphosphine derivative, and the reaction of the tetracarbonyl with dicyclohexylethylamine to produce y-butyrolactone... 

Insertion of carbon monoxide can also allow the formation of the C-C bond. For example, y-butyrolactones were produced by carbonylative cyclization of allenols [125] (Eq. 94). 

Buchwald and his group have also synthesized y-butyrolactones successfully by a metallocene mediated cyclization of enones (and ynones) with carbon monoxide in a formal [2-r2-rl]-ad-dition, and have thus achieved the first hetero-Pauson-Khand reaction [31]. The reactions can be conducted in high yields with either stoichio-metrical or catalytical amounts of [Cp2Ti(PMe,)2] as the example in Scheme 9 shows. 

It is interesting that upon illumination, the complex RhCl(CO)(PMc3)2 catalyzes carbonylation of liquified propane at room temperature to yield butanal with high regioselectivity [48], The reaction of some C-H compounds with carbon monoxide and ethylene or other olefins in the presence of metal carbonyls results in carbonylation at a C-H bond [49] (Scheme IV-25). The carbonyl Ru3(CO)i2 catalyzes the cyclocarbonylation of yne-aldehydes to bicyclic a,p-unsaturated y-butyrolactones [49d],... 

Burke discloses a two-step process for the conversion of butadiene to adipic acid at high yields [156]. The first step is the hydrocarboxylation of butadiene to form 3-pentenoic acid. The second step is the hydrocarboxylation of 3-pentenoic acid with carbon monoxide and water in the presence of a rhodium-containing catalyst, an iodide promoter, and certain inert solvents such as methylene chloride. The first reaction step gives also a significant by-product of y-valerolactone and a minor by-product of a-methyl-7-butyrolactone. These lactones can be converted to adipic acid by modified catalyst compositions [157-159]. In a related work, pentenic acids or esters are used as the starting intermediates for conversion to adipic acid [160-166]. 

Chatani N, Tobisu M, Asaumi T, Fukumoto Y, Murai S (1999) Ruthenium carbonyl-catalyzed [2- -2- -l]-cycloaddition of ketones, olefins, and carbon monoxide, leading to functionahzed y-butyrolactones. J Am Chem Soc 121 7160-7161... 

Diacids.— Dicarboxylic acids are obtained by the reaction of y-butyrolactones with carbon monoxide at atmospheric pressure and room temperature in HF-SbFs super acid media. A double-bond cleavage reaction of silyl enol ether using Mo02(acac)2 Bu OOH as oxidizing agent leads to a diacid in the case of (11) and to a ketoacid with (12) yields are high for the nine examples studied. ... 

Unlike epoxides, oxetanes react with carbon monoxide in the presence of Co2(CO)g by ring expansion to -y-butyrolactones, rather than ring opening thietanes (eq 18) as well as azetidines (eqs 19 and 20) behave similarly. Mixtures of cobalt and ruthenium carbonyls (1 1) are reported to give better yields than either catalyst separately. The examples shown illustrate the strong dependence of regioselectivity on substitution pattern in the aze-tidine case. ... 

Reactions of the (RC2H)Co2(CO)6 complexes with carbon monoxide under pressure give lactone complexes (reducible to y-butyrolactones ) by insertion of two CO groups into the Co-C bonds (eq 37) the further stepwise insertion of CO and alkyne provides the mechanism for the efficient Co2(CO)g-catalyzed synthesis of 2,2 -bifurylidene-5,5 -diones (eq 38). Under relatively mild conditions and with a 1 1 ratio of C2H2 CO, the extended bifurandiones of eq 39 also become significant products. ... 

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