Carbon dioxide reaction with organometallic

Tsai JC, Khan M, Nicholas KM (1989) Reactivity of coordinated carbon dioxide reactions of (C5H5)2Mo(.eta.2-C02) with electrophiles. Organometallics 8 2967-2968... 

The aryl bromides undergo facile metalation with butyl lithium to produce aryllithium derivatives with the expected organometallic activity.9 For example, reaction of lithiated PPO with carbon dioxide produces a carboxylated PPO which exhibits unique blending characteristics18. 

SCHORIG1N (or Shorygin) REACTION. Organometallic reactions of the Grignard type, employing sodium in place of magnesium the reaction of alkyl sodium compounds with carbon dioxide to give monobasic acids is sometimes known as the Wanklyn reaction. 

Carboxylic acid groups can also be installed in molecules using the reaction of an organometallic compound with carbon dioxide. This is a reductive method since the carbon dioxide is reduced to a carboxylic acid by formation of a new carbon-carbon bond. Both Grignard reagents and organolithium compounds work well in this reaction. 

Less attention has been paid, however, to C02 organometallic chemistry during the past decade. Whilst many reduction or coupling reactions are known to proceed in the presence of stoichiometric or catalytic amounts of transition metal complexes, very few examples remain where the formation of a metal-C02 complex has led to an effective, catalytic reduction reaction of C02. Carbon dioxide complex photoactivation also represents an attractive route to CO bond cleavage, coupled with O-atom transfer. However, progress in the area of C02 utilization requires a better understanding of the reaction mechanisms, of the thermodynamics of reaction intermediates, and of structure-reactivity relationships. 

It is also conceivable that, instead of the formation of Fe3(CO)u2- by reaction of Fe3(CO)12 with the quaternary ammonium hydroxide, attack by the latter at a carbonyl carbon of Fe3(CO)i2 could occur to give the hydroxycarbonyl species 7 (Scheme 4). Subsequent loss of carbon dioxide would afford the iron hydride. The intermediacy of organometallics... 

The reactions of organometallic 20 compounds of transition metals (29) with molecular nitrogen and carbon dioxide... 

This is an excellent reaction for the conversion of most halides to acids containing one additional carbon atom. Carbonation of Grignard reagents and organoalkali compounds gives acids in yields of 50-85%. Ether solutions of the organometallic compounds formerly were treated with carbon dioxide gas at 10° to -10°. A more recent technique involves pouring the solution onto excess crushed Dry Ice. Carbon dioxide... 

Because organometallic reagents are strong nucleophiles, they react with many other electrophiles in addition to carbonyl groups. Because these reactions always lead to the formation of new carbon-carbon bonds, they are also valuable in organic synthesis. In Section 20.14, we examine the reactions of organometallic reagents with carbon dioxide and epoxides. 

A mixture of 150 ml. of toluene, 11.5 g. (0.5 gram atom) of sodium sand, and 22.5 g. (0.2 mole) of chlorobenzene is stirred at room temperature under an atmosphere of dry nitrogen. After about 45 minutes an exothermic reaction sets in, and the temperature of the reaction mixture is held below 40° with a cooling bath. The entire reaction requires about 2 hours. The toluene solution of phenylsodium should be used immediately. (See preparation of benzylsodium, p. 32.) The yield of organometallic compound is 87%. The yield is determined from the amount of benzoic acid obtained after pouring the above solution on excess crushed solid carbon dioxide followed by acidification. 

The secondary reduction of the terminal radical by Sml2 generates samarium alkyl species which are suitable for classical organometallic reactions, e.g. protonation, acylation, reactions with carbon dioxide, disulfides, diselenides, or the Eschenmoser salt. A broad variety of products is available (hydroxy-substituted alkanes, esters, carboxylic acids, thioethers, selenoethers, tertiary amines) by use of the double-redox four-step (reduction-radical reaction-reduction-anion reaction) route (Scheme 20) [73]. 

The electrochemical incorporation of CO2 into perfluoroalkyl derivatives has been explored in the case of (perfluoroalkyl)alkyl iodides and (perfluoroalkyl)alkenes, with an electrochemical system based on the use of consumable anodes combined with organometallic catalysis by nickel complexes. Iodide derivatives have been functionalized to the corresponding carboxylic acids by reductive carboxylation. Interesting and new results have been obtained from the fixation of CO2 into perfluoroalkyl olefins. Good yields of carboxylic acids could be reached by a carefull control of the reaction conditions and of the nature of the catalytic system. The main carboxylic acids are derived from the incorporation of carbon dioxide with a double bond migration and loss of one fluorine atom from the CF2 in a position of the double bond. 

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