Syntheses of Dialkyl and Functionalized Ketones via 1-(Benzotriazol-1-yl)alkyl Methyl Thioethers
摘要:
Benzotriazol-1-ylmethyl methyl thioether (1), after easy deprotonation by BuLi, reacted with alkyl halides to afford 1-(benzotriazol-1-yl)alkyl methyl thioethers 2 in good yields. The utility of compounds 2 as alkanoyl anion equivalents was demonstrated by the reactions of their anions with alkyl halides, aldehydes, ketones, esters, and phenyl isocyanate: the products were readily hydrolyzed to alpha-functionalized ketones in dilute aqueous acid.
Synthesis ofcis andtrans Whisky and Cognac lactones by the regiocontrolled alkylation of 2-(trimethylsiloxy)furan
作者:Charles W. Jefford、Adam W. Sledeski、John Boukouvalas
DOI:10.1002/hlca.19890720625
日期:1989.9.20
The racemic cis- and trans-5-butyltetrahydro-4-methylfuran-2-ones ( = whisky lactones) and their higher homologues tetrahydro-4-methyl-5-pentylfuran-2-ones ( = cognac lactones) have been prepared in 2–3 steps from 2-(trimethylsiloxy)furan. Regioselective alkylation of the latter afforded the 5-butyl- and 5-pentylfuran-2(5H)-ones which served as precursors for the stereocontrolled construction of either
Regioselective alkylation of 2-trimethylsiloxyfuran; direct access to 4-substituted but-2-en-4-olides
作者:Charles W. Jefford、Adam W. Sledeski、John Boukouvalas
DOI:10.1039/c39880000364
日期:——
Primary iodides alkylate 2-trimethylsiloxyfuran in the presence of a molar excess of silver trifluoroacetate to give the 4-alkylbut-2-en-4-olides in 55–81% yield; as an illustration of the method, the cytotoxic marine sponge constituent, 4-(methoxycarbonylmethyl)but-2-en-4-olide was prepared in 79% yield in one step.
Radical addition of aldehydes and masked aldehydes like 1,3-dioxolanes to electron-deficient alkenes was achieved by the use of catalytic amounts of BPO and N-hydroxyphthalimide (NHPI) as a polarity-reversal catalyst under mild conditions. Three-component radical coupling of 1,3-dioxolanes, maleates, and alkenes was performed in the presence of BPO and NHPI under similar conditions. (C) 2003 Elsevier Ltd. All rights reserved.
JEFFORD, CHARLES W.;SLEDESKI, ADAM W.;BOUKOUVALAS, JOHN, HELV. CHIM. ACTA, 72,(1989) N, C. 1362-1370
作者:JEFFORD, CHARLES W.、SLEDESKI, ADAM W.、BOUKOUVALAS, JOHN
DOI:——
日期:——
JEFFORD, CHARLES W.;SLEDESKI, ADAM W.;BOUKOUVALAS, JOHN, J. CHEM. SOC. CHEM. COMMUN.,(1988) N 5, 364-365
作者:JEFFORD, CHARLES W.、SLEDESKI, ADAM W.、BOUKOUVALAS, JOHN