A Synthesis of the Chlorosulfolipid Mytilipin A via a Longest Linear Sequence of Seven Steps
作者:Won-jin Chung、Joseph S. Carlson、D. Karl Bedke、Christopher D. Vanderwal
DOI:10.1002/anie.201304565
日期:2013.9.16
Magnificent seven: The chlorosulfolipidmytilipin A was synthesized in racemic form in sevensteps and in enantioenriched form in eight steps. Key transformations include a highly diastereoselective bromoallylation of a sensitive α,β‐dichloroaldehyde, a kinetic resolution of a vinyl epoxide, a convergent and highly Z‐selective alkene cross‐metathesis, and a chemoselective and diastereoselective dichlorination
精彩七:氯硫脂 mytilipin A 以外消旋形式分七步合成,对映体富集形式分八步合成。关键转化包括敏感的 α,β-二氯醛的高度非对映选择性溴烯丙基化、乙烯基环氧化物的动力学拆分、会聚和高度Z选择性烯烃交叉复分解,以及复合二烯的化学选择性和非对映选择性二氯化。
A regio- and stereo-controlled synthesis of α,β-unsaturated carbonyl compounds
作者:Susumu Sato、Isamu Matsuda、Yusuke Izumi
DOI:10.1016/s0040-4039(00)98543-5
日期:——
rhodium(I) catalyzed isomerization of 1,3-diene monoepoxides and α-alkylidene-γ-butyrolactones, respectively. The former transformation is formally regarded as the equivalent of a regiospecific aldol condensation of an unsymmetricalketone.
Production of 2,5-Dihydrofurans and Analogous Compounds
申请人:Njardarson Jon
公开号:US20090131691A1
公开(公告)日:2009-05-21
Vinyl oxiranes are rearranged to 2,5-dihydrofuran using catalyst (III) or (IV). The 2,5-dihydrofuran can be reduced to tetrahydrofuran. 3,4-Epoxy-1-butene substrate is converted to 2,5-dihydrofuran which in turn is converted to tetrahydrofuran. Substrate for making 3-methyltetrahydrofuran is prepared from isoprene. Substrate for making 2-methyltetrahydrofuran is prepared from piperylene. Reactions analogous to that with vinyl oxiranes are carried out with vinyl thiiranes and vinyl aziridines.
Various gamma-heteroatom-substituted allylindium reagents were prepared, and their reactions with carbonyl compounds were examined. The reaction of 1,3-dibromopropene with metallic indium gave two types of organoindium species, gamma-bromoallylindium and allylic diindium reagents. While the former gave 2-phenyl-3-vinyloxirane upon the coupling with benzaldehyde, the latter gave 1-phenylbut-3-en-1-o1. 1-Iodo-3-bromopropene gave the homoallylic alcohol exclusively. gamma-Alkoxyallylindium reagents were prepared by treating the corresponding gamma-alkoxyallyllithium with indium trichloride and reacted with benzaldehyde to give vic-diol mono ethers in high yields with good syn selectivity. gamma-(Trimethylsilyl)allylindium and alpha,gamma-disubstituted allylindium reagents were also prepared via transmetalation with the corresponding allyllithium.
SATO, SUSUMU;MATSUDA, ISAMU;IZUMI, YUSUKE, J. ORGANOMET. CHEM., 359,(1989) N, C. 255-266