Tandem SN2-Michael reactions for the preparation of simple five- and six-membered-ring nitrogen and sulfur heterocycles
作者:Richard A. Bunce、Christopher J. Peeples、Paul B. Jones
DOI:10.1021/jo00032a025
日期:1992.3
A one-pot tandem S(N)2-Michael addition sequence has been developed for the preparation of five-membered- and six-membered-ring nitrogen and sulfur heterocycles from 6- or 7-halo-2-alkenoate esters. Nitrogen-containing rings are prepared by reaction of the omega-halo-2-alkenoate ester with a primary amine in the presence of triethylamine. The sulfur analogues are generated by thiourea displacement of the halide followed by base hydrolysis of the isothiouronium salt. Yields are routinely in the 60-80% range. Experiments are described which elucidate the chronology of the reaction sequences. Ring size and steric hindrance to the initial substitution reaction appear to be the only limitations of the procedure.
BECKWITH, A. L. J.;EASTON, CH. J.;LAWRENCE, T.;SERELIS, A. K., AUSTRAL. J. CHEM., 1983, 36, N 3, 545-556
作者:BECKWITH, A. L. J.、EASTON, CH. J.、LAWRENCE, T.、SERELIS, A. K.
DOI:——
日期:——
PATTENDEN, GERALD;TEAQUE, SIMON J., TETRAHEDRON, 43,(1987) N 23, 5637-5652
作者:PATTENDEN, GERALD、TEAQUE, SIMON J.
DOI:——
日期:——
Beckwith, Athelstan L. J.; Easton, Christopher J.; Lawrence, Tony, Australian Journal of Chemistry, 1983, vol. 36, # 3, p. 545 - 556
作者:Beckwith, Athelstan L. J.、Easton, Christopher J.、Lawrence, Tony、Serelis, Algirdas K.
DOI:——
日期:——
Transannular cyclisation as a stratagem in synthesis. A total synthesis of (±)-pentalenene
作者:Gerald Pattenden、Simon J. Teague
DOI:10.1016/s0040-4020(01)87743-7
日期:1987.1
A total synthesis of the triquinane sesquiterpene (±)-pentalenene(1) found in Streptomyces, based on transannularcyclisation of the bicyclo [6.3.0] undecadiene (7) in the presence of boron trifluoride etherate is described. The bicyclo(6.3.0]undecadiene(7) was elaborated from the silyl enol ether(36) using a unique intramolecular [2+2] photocycloaddition - Grob fragmentation sequence leading to (8)