Organolithiums dioxide

The reactions of organolithium compounds with carbonyl compounds, including carbon dioxide, may be interpreted as follows ... 

Lithium cobalt dioxide, uses, 7 24 It Lithium complex greases, 15 243 Lithium compounds, 20 598-599. See also Organolithium compounds inorganic, 15 136-142 uses for, 15 134 Lithium cyanide, 8 194 Lithium 5—alumina, 2 406t... 

Scheme 2.38 Functionalized allenes formed by 1,4-addition of organolithium reagents to enynes and electrophilic trapping with aldehydes (111, 112) ketones (113,114), ethylene oxide (115) and carbon dioxide (116).

Carbonation. The carbonation of polymeric organolithium compounds using carbon dioxide is one of the most useful functionalization reactions. However, there are special problems associated with the carbonation of polymeric organolithium compounds. For example,... 

Wyman, Allen and Altares (20) reported that the carbonation of poly-(styryl)lithium in benzene with gaseous carbon dioxide produced only a 60% yield of carboxylic acid the acid was contaminated with significant amounts of the corresponding ketone (dimer) and tertiary alcohol (trimer) as shown in eq. 6. A recent, careful, detailed investigation of the carbonation of polymeric organolithium compounds has... 

Functionalized organolithium intermediates 412-417, can be used as synthones for addition to various substrates containing the C=C—C=0 moiety or for dimerization via the C—Li bonds, all catalyzed by Cu(I) and Cu(II) salts . They may also be exposed to various electrophiles for example, intermediate 412 reacts with carbon dioxide as shown in equation 115, to yield a lactone (418) as the only product after workup. ... 

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. 

Fig. 6.45. Chemoselective acylation of organolithium compounds with lithium-carboxylates (A). In order to generate the substrates the choice is between the deprotonation of the corresponding carboxylic acid and the addition of an organolithium compound to carbon dioxide, i.e. via C,C bond formation.

The organolithium compound (214) is obtained by treatment of the tetrathiafulvalene (5) with lithium diisopropylamide (LDA). This lithium compound (214) can further react with carbon dioxide, ethyl chloroformate, acetyl chloride, formaldehyde, dimethyl sulfate, and triethyloxonium hexafluorophosphate to produce the correspondingly substituted tetrathiafulvalenes (215) (79JOC1476). 

The following procedure [1] is typical, and other similar examples have been described [2] (see also General Ref. [A] for an account of earlier work). An alternative procedure is that described for organolithium compounds (see General Ref. [G], p. 142) [3], in which the Grignard reagent is added to a solution of liquid sulfur dioxide in ether at -78°. 

Several 1,1-dichloro-, 1,1-dibromo- and 1-bromo-l-fluorocyclopropanes have been transformed to the corresponding a-halocyclopropanecarboxylic acids by sequential treatment with an organolithium reagent, usually butyllithium, at low temperature, carbon dioxide, and a mineral acid. The yields are often moderate to low, but surpass 80% in exceptional cases. 

Addition of organolithiums to carbon dioxide affording lithium carboxylates, thence carboxylic acids, is a ery familiar reaction [32]. 

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