Carbon monoxide, reaction with organic halides

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. 

Numerous metal-catalyzed reactions of organic halides with carbon monoxide and olefins, acetylenes, aldehydes, etc., have been carried out (21). Only two of these, however, appear to have been developed into generally useful reactions. One is the reaction of allylic halides with carbon monoxide and acetylene in alcoholic solution with a nickel catalyst (22,23). This reaction produces cis-2,5-hexadienoate esters at atmospheric pressure in good yields ... 

Oxidizer, Poison, Corrosive SAFETY PROFILE Poisonous and corrosive. Very reactive, a powerful oxidizer. Explosive or violent reaction with organic materials, water, acetone, ammonium halides, antimony, antimony trichloride oxide, arsenic, benzene, boron, bromine, carbon, carbon monoxide, carbon tetrachloride, carbon tetraiodide, chloromethane, cobalt, ether, halogens, iodine, powdered molybdenum, niobium, 2-pentanone, phosphoms, potassium hexachloroplatinate, pyridine, silicon, silicone grease, sulfur, tantalum, tin dichloride, titanium, toluene, vanadium, uranium, uranium hexafluoride. 

Heck RF. Transition metal-catalyzed reactions of organic halides with carbon monoxide, olefins, and acetylenes. Adv. Catal. 1977 26 323-349. 

The cross-coupling reaction of organoboron compounds with organic halides or triflates proceeds selectively in the presence of a base, such as sodium or potassium carbonate, phosphate, hydroxide, and alkoxide [11, 45], The bases can be used in aqueous solution, or in suspension in dioxane or DMF. In contrast, the cross-coupling reaction with certain electrophiles, such as allylic acetates [45], 1,3-butadiene monoxide [49], and propargyl carbonates [50], occurs under neutral conditions without any assistance from a base. The transmetallation of organoboron compounds with palladium halides under basic or neutral conditions can be considered to involve three routes, 1, 2, and 3 (Schemes 2-18, 2-20, and 2-23, below). 

The anions generated from tetracarbonyl(phosphine) carbene complexes are more reactive in their reactions with organic electrophiles. This is consistent with the observation that the pATa of the methyl pentacarbonyl complex (88a) is increased by six orders of magnitude when one of the carbon monoxide ligands is replaced with tributylphosphine. The anion generated from (106) will give good yields of alkylated products with simple alkyl halides such as ethyl bromide however, dialkylation is still a serious side reaction. It has been reported that both pentacarbonyl and tetracarbonyl(phosphine) complexes can be efficiently monoalkylated with alkyl triflates (primary and secondary). The anion (89) for example, can be monoalkyated with the 3-butenyl triflate in 80% yield. ... 

Metal-Catalyzed Reactions of Organic Halides with Carbon Monoxide, Olefins, and Acetylenes. 

Palladium-Catalyzed Ring-Forming Reactions of Organic Halides with Unsaturated Substrates and Carbon Monoxide. 

An attractive pathway with a lot of potential uses the transition metal mediated reaction of organic halides with carbon monoxide. Suitable substrates are organic halides capable of oxidative addition to low-valent transition metal compounds. Insertion of carbon monoxide and reductive elimination of an acid halide will complete the catalytic cycle. In tins way it was shown tiiat allyl chloride yields butenoic acid chloride in >80% yield accor g to equation 22)P As well as palladium, rhodium and iridium also act catalytically. It is of no surprise that allylic halides, benzylic halides and aryl halides in particular are readily converted to acid halides. Simple aliphatic halid undergo the oxidative addition step more slowly and, if they cany hydrogen atoms on an sf hybridized C atom in the -position to the halogen atom, may give alkenes via 3-hydrogen elimination. Alkenes can also be converted to acid halides widi carbon monoxide in the presence of transition metal catalysts in solvents such as methylene chloride or tetrachloromethane. ... 

Unsymmetrical ketones can be readily synthesized by the reaction of organic halides with organotin compounds and carbon monoxide in the presence of catalytic amounts of [PhPdI(PPh3)2] [equation (14)]. Although only simple... 

A60. J. P. Candlin, K. A. Taylor, and D. T. Thompson, "Reactions of Transition-Metal Complexes. Elsevier, Amsterdam, 1968. A review of types of reactions of metal complexes (e.g., substitution, combination, redox) reactions with various reagents (e.g., hydrocarbons, halides, carbon monoxide, and isonitrile) and preparation of new stabilised organic systems (e.g., metallocenes, carbenes). Intended for research workers, consequently written at a fairly high level, with emphasis on organometallics. A61. H. J. Keller, NMR-Untersuchungen an Komplexverbindungen. Springer, Berlin, 1970. Expansion of review article 37.1. 

Coupling of organostannanes with halides in a carbon monoxide atmosphere leads to ketones by incorporation of a carbonylation step.249 The catalytic cycle is similar to that involved in the coupling of alkyl or aryl halides. These reactions involve Reactions involving a migration of one of the organic substituents to the carbonyl carbon, followed by... 

Examples are given of common operations such as absorption of ammonia to make fertilizers and of carbon dioxide to make soda ash. Also of recovery of phosphine from offgases of phosphorous plants recovery of HF oxidation, halogenation, and hydrogenation of various organics hydration of olefins to alcohols oxo reaction for higher aldehydes and alcohols ozonolysis of oleic acid absorption of carbon monoxide to make sodium formate alkylation of acetic acid with isobutylene to make fert-butyl acetate, absorption of olefins to make various products HCl and HBr plus higher alcohols to make alkyl halides and so on. 

A more versatile palladium-catalyzed formylation of organic halides takes place using tributyltin hydride and carbon monoxide (equation 7). The reaction works for a variety of substrates — aryl, benzyl and vinyl iodides, vinyl triflates and allyl halides. Reaction conditions are mild (1-3 bar CO, 50 °C), and a variety of functional groups can be tolerated. With unsymmetrical allyl halides formylation is regio-selective, taking place at the less-substituted allylic position with retention of geometry at the allylic double bond. 

K4[Ni2(CN)6] has a dimeric structure with Ni-Ni bond 64). The usefulness of this complex is apparent from its ready reaction with a variety of organic halides by splitting of the Ni-Ni bond. For example, the complex reacts with benzyl bromide to form a o-bond and then undergoes coupling reaction or carbon monoxide insertion to give ketone 65 65a>. 

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