From carbon monoxide reaction with Group

Following the first observations by Heck that Pd(OAc)2 can substitute a hydrogen atom in ethylene by a carbomethoxy group [50], Stille and James have discovered that the [Pd - Cu] couple catalyzes the incorporation of a COOMe group arising from carbon monoxide and methanol [51]. Most of the reactions with an alkene end up with a diester or a methoxyester, copper being used in stoichiometric quantities. Cyclic alkenes give preferentially diesters (Scheme 7). 

Formamides are usually not deprotonated a to nitrogen but at the formyl group [227-231], The resulting carbamoyl lithium derivatives (R2NCOLi), which can also be generated from deprotonated amines [351] or amides [352] and carbon monoxide, react with electrophiles E+ to yield the expected products (R2NCOE), despite the carbene character and consequent low stability of these intermediates [179, 351] (Scheme 5.39, see Section 5.4.7). Palladium-catalyzed versions of the reaction have been reported [353, 354],... 

Alkenyl complexes. These complexes are prepared by reaction of an alkenyllithium with Cr(CO)6 followed by methylation. These a,(l-unsaturated complexes react with terminal alkynes to give, after oxidative work-up, phenols or quinones in which the acetylene group is ortho to the phenolic hydroxyl group derived from carbon monoxide. 

Let s begin our analysis of this cycle by examining what is required in the reaction. Logically, the C=0 in acetic acid comes from carbon monoxide, while the methyl group comes from the methanol. Therefore, CO has inserted into the C-O bond in methanol. This, in turn, requires that Rh has inserted into the methanol C-O bond, or an equivalent bond, at some point in the mechanism. With these ideas in mind, we can start to analyze a logical pathway for this cycle (Figure 12.12). 

The addition of alcohols to form the 3-alkoxypropionates is readily carried out with strongly basic catalyst (25). If the alcohol groups are different, ester interchange gives a mixture of products. Anionic polymerization to oligomeric acrylate esters can be obtained with appropriate control of reaction conditions. The 3-aIkoxypropionates can be cleaved in the presence of acid catalysts to generate acrylates (26). Development of transition-metal catalysts for carbonylation of olefins provides routes to both 3-aIkoxypropionates and 3-acryl-oxypropionates (27,28). Hence these are potential intermediates to acrylates from ethylene and carbon monoxide. 

Organopalladium intermediates are also involved in the synthesis of ketones and other carbonyl compounds. These reactions involve acylpalladium intermediates, which can be made from acyl halides or by reaction of an organopalladium species with carbon monoxide. A second organic group, usually arising from any organometallic reagent, can then form a ketone. Alternatively, the acylpalladium intermediate may react with nucleophilic solvents such as alcohols to form esters. 

The polymers prepared from thexylborane and diene monomers were reacted with carbon monoxide at 120°C, followed by treatment with NaOH and H202 to produce a polyalcohol (scheme 5).13 This conversion includes migration of the polymer chain and thexyl group from the boron atom to carbon, as shown in scheme 5. When this reaction was carried out under milder condition, poly(ketone) segments were included in the polymer backbone due to an incomplete migration of the thexyl group. 

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