METHYL 7-OXOOCTANOATE

NUCLEOPHILIC ACYLATION WITH DISODIUM TETRA-CARBONYLFERRATE METHYL 7-OXOHEPTANOATE AND METHYL 7-OXOOCTANOATE... 

Methyl 7-oxooctanoate Octanoic acid, 7-oxo-, methyl ester (8,9) (16493-42-8)... 

The product of Part B of this procedure, methyl 7-oxoheptanoate, has previously been synthesized from cyclohep-tanone in two steps with a 42% overall yield." 7-Oxooctanoic acid, the methyl ester of which is the product of Part C, has been prepared by base-induced ring cleavage of 2-acetylcyclo-hexanone."... 

Methyl 8-oxooctanoate-4,5-D2, 35, and methyl 12-oxododecarbate-4,5,8,9-D4, 36, have been synthesized32 as shown in equations 13 and 14 by monoozonization and sodium acetate cleavage of 1,5-cyclooctadiene and 1,5,9-cyclododecatriene, respectively. The resultant unsaturated aldehydic acids 37 and 38 have been converted to the corresponding acetal esters, which have been deuteriated with Wilkinson s catalyst33 and hydrolysed to the deuterium-labelled aldehydic esters 35 and 36 in 47% and 49% overall yields and... 

Capillary gas chromatographic investigation of diastereoisomeric derivatives revealed that in analogy to results obtained without precursors the chiral metabolites are present as mixtures of enantiomers. However for only a few of these compounds the ratios of enantiomers are identical with those determined in pineapple without precursors. The enantiomeric compositions of ethyl 3-hydroxyhexanoate and ethyl 3-acetoxyhexanoate are almost opposite to those determined for the naturally occurring methyl esters. 6-Octalactone obtained after addition of 5-oxooctanoic acid to pineapple tissue is almost optically pure (92% S) on the other hand -octalactone is naturally present in pineapple tissue as nearly racemic mixture (Table 1,8). 

To contrast with the preceding strategies, 2-methoxycarbonylresorcinol compounds can be synthesised from the bis-trimethylsilyl derivative of methyl acetoacetate and the dimethyl acetal of methyl 3-oxooctanoate (ref.28). 

As with oleate, some volatile decomposition compounds are formed from linoleate hydroperoxides that cannot be explained by the classical A and B cleavage mechanism, including acetaldehyde, 2-pentylfuran, methyl heptanoate, 2-octenal, 2,4-nonadienal, methyl 8-oxooctanoate, and methyl 10-oxodecanoate. Although hydroperoxides derived from both autoxidation and from photosensitized oxidation of linoleate form the same volatile decomposition products, significant quantitative differences are noted. The autoxidized linoleate hydroperoxides produced more pentane, 2-pentyl furan, 2,4-decadienal and... 

Butyric acid, octanoic acid, oleic acid, succinic acid, octadecanoic acid, eicosanoic acid, tetracosanoic acid, hexadecanoic acid, 7-oxooctanoic acid, 3-methyl-3-hydroxyglutaric acid, 9,10-dihydroxy-2-decenoic acid, 9,10-dihydroxydodecanoic acid, 9-oxo-2-decenoic acid (9-ODA), 11,12-dihydroxy-2-dodecenoic acid, 13- hydroxy-2-tetradecenoic acid, 2-hydroxyoctanoic acid, 3-methyi-3-hydroxygiutaric acid, 14- hydroxytetradecanoic acid [16] 5,10-Dihydroxydecanoic acid, 8,9-dihydroxydecanoic acid, 3-hydroxydecanedioic acid, 1,12-dodecanedioic acid, 7-hydroxy-2-octenoic acid, 3,10-dihydroxydodecanoic acid, 8-hydroxy-2-octenoic acid, 2-octene-1,8-dioic acid, 8-hydroxy-2-decenoic acid, (Z)-9-hydroxy-2-decenoic acid, ( -9-HDA, 3,9-dihydroxydecanoic acid, 8,9-dihydroxydecanoic acid, 10- hydroxy-2-dodecenoic acid, 11- hydroxy-2-dodecenoic acid, 3-hydroxydecanedioic acid, 1,12-dodecanedioic acid, 10,12-dihydroxydodecanoic acid [16,17]... 

Dimelhyl-2-butene added at 0° to 3.1 M borane in tetrahydrofuran to form thexylborane (2,3-dimethyl-2-butylborane), stirring continued 1 hr. at 0°, a soln. of isobutylene in tetrahydrofuran added and allowed to react 0.5 hr. at 0°, then ethyl vinylacetate added, allowed to stand 2 hrs. at 0°, water added, kept 3 hrs. at 50° under 70 atm. GO in a stainless-steel autoclave, transferred to a glass flask, 3 M Na-acetate added followed by O -HgOg at a rate to maintain the temp, at 30-40°, and kept 1 hr. at 50° — ethyl 7-methyl-5-oxooctanoate. Y 84%. - Because of the low migration aptitude of the thexyl group, either the same or two different olefins with a wide variety of functional groups can... 

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