The synthesis of simple alkyl substituted spiroacetals by α,α′-alkylation of metalated acetone dimethylhydrazone with appropriate electrophiles and subsequent acid catalyzed cleavage and ring closure of the products is described.
Studies on reductive alkylation: Synthesis of Wieland-Miescher ketone analogues bearing an oxygenated angular substituent
作者:L.N. Mander、R.J. Hamilton
DOI:10.1016/s0040-4039(01)82080-3
日期:1981.1
Wieland-Miescheranalogues 2a and 2b have been prepared in good yield by a sequence utilising reductive alkylation of the dihydro aromatic ester enolate 7d, which functions as a synthetic equivalent of the dioxo ester 5 anion; these analogues are envisaged as intermediates in a projected synthesis of bruceantin.
Spiroacetals and Other Venom Constituents as Potential Wasp Attractants
作者:Roderick J. Weston、Anthony D. Woolhouse、Eric B. Spurr、Richard J. Harris、D. Max Suckling
DOI:10.1023/b:joec.0000006396.55680.b6
日期:1997.3
The major volatile spiroacetals from the venom of both the common wasp, Vespula vulgaris and the German wasp V. germanica, viz. 7-methyl-1,6-dioxaspiro[4,5]decane and 7-ethyl-2-methyl-1,6-dioxaspiro[4,5]decane, respectively, were synthesized by known methods. These acetals, along with N-isopentylacetamide (the major volatile amide from wasp venom), 2-heptanone (a honeybee pheromone), 2-methyl-3-buten-2-ol (a component of hornet venom), cuticle wax from V. vulgaris, and venom sacs from both wasp species were assayed by EAG and olfactory bioassay for attractancy to V. vulgaris workers. Antennal responses to all test chemicals were recorded. Acetal isomers (+/-)-2 and (+/-)-3, N-isopentylacetamide, and 2-heptanone were attractive to V. vulgaris workers at levels of <1 mu mol. Greater quantities of the same compounds were repellent to V. vulgaris workers.
Improved methods for the reductive alkylation of methoxybenzoic acids and esters: applications to the synthesis of bicyclic ketones
作者:Robert J. Hamilton、Lewis N. Mander、S.Paul Sethi
DOI:10.1016/s0040-4020(01)90577-0
日期:1986.1
employed to introduce the elements of a butanone or pentanone side-chain as a prelude to adding a fused six-membered ring, thereby completing the preparation of several analogues of the Wieland-Miescher ketone 4a in which the angular substituent was oxygenated.