Oxidation of olefins with 2-pyridineseleninic anhydride
作者:Derek H.R. Barton、David Crich
DOI:10.1016/s0040-4020(01)97207-2
日期:1985.1
2-Pyridineseleninic anhydride, prepared in situ by oxidation of the corresponding diselenide with iodoxybenzene, is an efficient reagent for the conversion of olefins to unsaturated ketones with retention of the original position of the double bond. This reagent is, therefore, much more reactive towards olefins than benzeneseleninicanhydride. An explanation has been offered.
(1) Oxidation of dl-α-terpineol with tert-butyl chromate yeilded 8-hydroxypiperitone, which has not previously been described, 8-hydroxycarvotanacetone and homoterpenyl methyl ketone. In this case the oxidative fission of the double bond in the ring took place to a remarkable extent.(2) Oxidation of dl-α-terpinyl acetate with tert-butyl chromate gave 8-acetoxypiperitone, 8-acetoxycarvotanacetone, (neither have previously been described) and homoterpenyl methyl ketone. In this oxidation the cleavage of the ethylenic linkage was suppressed, and the yield of 8-acetoxycarvotanacetone was relatively good.Moreover, the effects of the solvent, acetic acid, benzoyl peroxide, air and the reaction temperature, on the yield of 8-acetoxycarvotanacetone wre investigated.(3) 8-acetoxycarvotanacetone was converted into dl-carvone when acetic acid was eliminated by pyrolysis.(4) The synthesis of carvone from α-terpinyl acetate was attiained through the intermeidate of 8-acetoxycarvotanacetone The overall of carvone from α-terpinyl acetate was 28% mole%.
THE STEREOSPECIFIC HYDROXYLATION OF ENDOCYCLIC ETHYLENIC LINKAGE IN THE BIOTRANSFORMATION OF α-TERPINYL ACETATE WITH CULTURED SUSPENSION CELLS OF<i>NICOTIANA TABACUM</i>
作者:Toshifumi Hirata、Ym Sook Lee、Takayuki Suga
DOI:10.1246/cl.1982.671
日期:1982.5.5
The biotransformation of (±)-8-acetoxy-p-menth-1-ene (α-terpinyl acetate) with the culturedcells of Nicotianatabacum was found to result in the predominant formation of 8-acetoxy-c-4-p-menthane-r-1,t-2-diol. This experimental result indicates that the hydroxylation of the endocyclic ethylenic linkage with the culturedsuspensioncells is stereospecific.
Lithium Cobalt-Bis-Dicarbollide: A Novel Lewis Acid Catalyst for the Conjugate Addition of Silyl Ketene Acetals to Hindered .alpha.,.beta.-Unsaturated Carbonyl Compounds
作者:William J. DuBay、Paul A. Grieco、Lee J. Todd
DOI:10.1021/jo00102a009
日期:1994.11
The novel Lewis acid, lithium cobalt-bis-dicarbollide (1), in which the lithium ion is weakly coordinated to the Co(B9C2H11)(2)(1-)anion, is an effective, soluble catalyst for Mukaiyama-Michael reactions.
Matsuura et al., Nippon Kagaku Zasshi, 1957, vol. 78, p. 1122