Allylic derivatives carbon monoxide reactions

The allylic nitrogen derivatives, such as allylic ammonium salts, tosylimides, and nitro compounds, react with Pd(0) species under mild reaction conditions to form rr-allylpalla-dium intermediates, which undergo coupling reaction with various nucleophiles to give allylated nucleophiles. Carbon monoxide reacts with the 7r-allylpalladium species derived from allylamines to give /3,y-unsaturated amides. 

Treatment of the 1,2-oxazines 52 with carbon monoxide at 1000 psi in the presence of cobalt carbonyl brings about insertion of carbon monoxide to form the 1,3-oxazepines S3 <96TL2713>. A convenient route to P-lactams fused to oxepines is made available by alkene metathesis. Thus reaction of 4-acetoxyazetidin-2-one with ally alcohol in the presence of zinc acetate, followed by iV-allylation of the nitrogen affords the derivative 54 which cyclises by RCM to form the oxazepinone 55 <96CC2231>. The same communication describes a similar synthesis of 1,3-dioxepines. 

Allyl methylcarbonate reacts with norbornene following a ruthenium-catalyzed carbonylative cyclization under carbon monoxide pressure to give cyclopentenone derivatives 12 (Scheme 4).32 Catalyst loading, amine and CO pressure have been optimized to give the cyclopentenone compound in 80% yield and a total control of the stereoselectivity (exo 100%). Aromatic or bidentate amines inhibit the reaction certainly by a too strong interaction with ruthenium. A plausible mechanism is proposed. Stereoselective CM-carboruthenation of norbornene with allyl-ruthenium complex 13 followed by carbon monoxide insertion generates an acylruthenium intermediate 15. Intramolecular carboruthenation and /3-hydride elimination of 16 afford the -olefin 17. Isomerization of the double bond under experimental conditions allows formation of the cyclopentenone derivative 12. 

In the carbonylation reactions, further reaction of the acyl lithium compounds with carbon monoxide can occur, but clean reaction can be achieved if the lithium amide is first converted to a copper derivative (Scheme 130) (79JOC3734). In the case of morpholine, reaction with allyl bromide gave a 93% overall yield of the amide product. 

REPPE PROCESS. Any of several processes involving reaction of acetylene (1) with formaldehyde to produce 2-butync-l,4-diol which can be converted to butadiene (2) with formaldehyde under different conditions to produce propargyl alcohol and, form this, allyl alcohol (3) with hydrogen cyanide to yield acrylonitrile (4) with alcohols to give vinyl ethers (5) with amines or phenols to give vinyl derivatives (6) with carbon monoxide and alcohols to give esters of acrylic acid (7) by polymerization to produce cyclooctatetraene and (8) with phenols to make resins. The use of catalysis, pressures up to 30 atm, and special techniques to avoid or contain explosions are important factors in these processes. 

Organic isocyanates and isothiocyanates as well as nitric oxide insert similady (412). Carbon monoxide inserts to yield very stable acyltitamums (412,413). Miscellaneous Reactions of CpfTi Derivatives. Coupling of fluxional pentadienide ion with allyl bromide is regiospecificatly catalyzed by Cp2TiCl2 (414,415). In contrast, cuprous chloride gives the linear triene ... 

It has been noted that unlike the palladium and platinum complexes, the nickel derivatives afford nickel iodide instead of the free metal. The reaction is accompanied by carbon monoxide evolution, which is increased in the presence of iodine. Independently of the stoichiometric ratio of Pd to Fe employed, the reaction consumes approximately half the amount of allyl-palladium compound. Hence the present authors assume that iron enneacarbonyl produces two moieties under the conditions of reaction ... 

The reaction of 3,3-dimethylcyclopropene with a number of metal derivatives in the presence of carbon monoxide resulted in ring opening, e.g. to allylic esters with a one-carbon homologation of the chain. 

Metal-carbon (M—C) bonds are thermodynamically unstable with regard to their hydrolysis products. Water can attack M—C bonds either by proton transfer (H+, electrophilic reaction) or via the oxygen (OH2 or OH, nucleophilic reaction). Examples are shown in Scheme 1. Ligands such as carbon monoxide and ethylene are activated toward nucleophilic attack upon coordination to (low-valent) metals, e.g., Pd2+. A number of C—C-bond forming reactions derive from this activation. Allyl ligands are generated by proton attack to the terminal 1,3-diene carbon... 

The catalytic [2 + 2 + 1]-cycloaddition reaction of two carbon—carbon multiple bonds with carbon monoxide has become a general synthetic method for five-membered cyclic carbonyl compounds. In particular, the Pauson-Khand reaction has been widely investigated and established as a powerful tool to synthesize cyclopentenone derivatives.110 Various kinds of transition metals, such as cobalt, titanium, ruthenium, rhodium, and iridium, are used as a catalyst for the Pauson-Khand reaction. The intramolecular Pauson-Khand reaction of the allyl propargyl ether and amine 91 produces the bicyclic ketones 93, which bear a heterocyclic ring as shown in Scheme 31. The reaction proceeds through formation of the bicyclic metallacyclopentene intermediate 92, which subsequently undergoes insertion of CO to give 93. 

VL3 Migratory Insertion Reactions of Allyl, Propargyl, and Allenylpalladium Derivatives Involving Carbon Monoxide and Related Derivatives... 

Reaction of Na[Mn(CO)s] with allyl chloride yields the yellow air-sensitive liquid CH2==CHCH2Mn(CO)5 with an allyl group cr-bonded to a manganese pentacarbonyl residue in the usual manner (99, 100). Heating this allylmanganese pentacarbonyl derivative to 80-90° C causes it to lose one mole of carbon monoxide to form w-allylmanganese tetracarbonyl (XXII), a yellow volatile crystalline solid, m.p. 52-53.5° C (99,100). Similar... 

In analogy to allyl halogenides, iodobenzene and other aromatic iodo derivatives can be reacted with Ni(CO)4 and acetylene at reaction temperatures above 100 °C with formation of y-ketoacids or their esters [418, 442], which may be considered as hydrolysis products of p,y-unsaturated y-lac-tones or as hydrogenation products of a,p-unsaturated y-ketoacids or -esters. a,p-Unsaturated y-ketoacids or -esters will be hydrogenated under the reaction conditions, but do not take up carbon monoxide because of the presence of electrophilic substituents. Besides allyl halogenides, allyl alcohols, -ethers and -esters may also be reacted to give unsaturated acids or esters. 

Palladium is a useful catalyst in several reactions which lead to keto-esters. p-Keto-esters react with allylic carbonates, with catalysis by palladium, in a decarboxylative allylation reaction. y-Keto-esters are prepared, in reasonable yield, by the palladium-catalysed regioselective oxidation of Py-unsaturated esters. y-Keto-esters are obtained in good yield by the palladium-catalysed Reformatsky reaction of ethyl bromoacetate and acid chlorides. Derivatives of y-ketopimelic acid are formed by the rhodium-carbonyl-catalysed reaction of derivatives of acrylic acid with carbon monoxide. A mild method for the conversion of propiolic esters into P-keto-esters via thiol addition has been reported (Scheme 63) it has been used in a formal synthesis of ( )-thienamycin. 

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