Ethyl cyclooctene-2-carboxylate

On the basis of theoretical studies by Bach and co-workers,17 it was found that the nucleophilic 71-bond of the alkene attacks the 0-0 cr-bond in an Sn2 fashion with displacement of a neutral carboxylic acid. There are, however, some mechanistic anomalies. For example, a protonated peracid should be a much more effective oxygen transfer agent over its neutral counterpart, but experiments have shown only modest rate enhancements for acid catalysed epoxidation. Early attempts to effect acid catalysis in alkene epoxidation where relatively weak acids such as benzoic acid were employed proved unsuccessful.18 The picture is further complicated by contradictory data concerning the influence of addition of acids on epoxidation rates.19 Trichloroacetic acid catalyses the rate of epoxidation of stilbene with perbenzoic acid, but retards the rate of a double bond containing an ester constituent such as ethyl crotonate.20 Recent work has shown that a seven-fold increase in the rate of epoxidation of Z-cyclooctene with m-chloroperbenzoic acid is observed upon addition of the catalyst trifluoroacetic acid.21 Kinetic and theoretical studies suggest that the rate increase is due to complexation of the peroxy acid with the undissociated acid catalyst (HA) rather than protonation of the peroxy acid. Ab initio calculations have shown that the free energy of ethylene with peroxy-formic acid is lowered by about 3 kcal mol-1 upon complexation with the catalyst.21... 

A screening of ruthenium(II) carboxylates and several ruthenium(II) chloride complexes has identified tetrakis(trifluoroacetato)diruthenium as an excellent catalyst for the cyclo-propanation of cyclooctene with ethyl diazoacetate (60°C, excess of alkene, 0.75 mol% of catalyst yield of ethyl bicyclo[6.1,0]nonane-9-carboxylate 99% endojexo 1.65)." With several other ruthenium(II) complexes, ring-opening metathesis polymerization of cyclooctene competes strongly with the cyclopropanation reaction. 

Cycloocta- diene-1,5 Chloro- ethanol Pd(P(C,H4)3),Cl2 Ethyl 2-chloro cyclooctene-4-carboxylate 37 [448]... 

An all-trons structure was assigned to poly(endo,endo-N,N-(norborn-5-ene-2,3-dicarbimido)-L-valine ethyl ester) (Scheme 8.11). Finally, Wagener et al. published details of the formal synthesis of poly(ethylene-co-vinyl alcohol), poly(ethylene-co-vinyl acetate), poly (ethylene-co-methylacrylate) and poly(ethylene-co-acrylic acid) copolymers, obtained via the ROMP of cyclooctene with hydroxy-, acetoxy-, methoxy-carbonyl and carboxylate-functionahzed cyclooctenes, followed by hydrogenation... 

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