The 4-exo-dig and 5-exo-dig cyclocarbopalladations have been efficiently used to produce molecular complexity in a straightforward manner. Strained 1,2-cyclobutanediols are rapidly obtained undermicrowaveirradiation in high yields. In many cases, the cyclocarbopalladation cascade reaction is associated with a 6 or 8π electrocyclic reaction. During the process of the 5-exo-dig cyclocarbopalladation
Alkynyliodonium Salts in Organic Synthesis. Dihydrofuran Formation via a Formal Stevens Shift of a Carbon Substituent within a Disubstituted-Carbon Oxonium Ylide
作者:Ken S. Feldman、Michelle Laci Wrobleski
DOI:10.1021/jo0011080
日期:2000.12.1
and 1-pyranyl ethers of 1-hydroxybut-3-ynyl(phenyl)iodonium triflate triggers a sequence of reactions that ultimately delivers 2-substituted 3-p-toluenesulfonyldihydrofuran products in variable yields. A putative 1,2-group shift within an unsaturated oxonium ylide (Stevens rearrangement) accounts for the oxygen-to-carbon transfer of the ether substituent. Deuterium labeling studies clarify the mechanistic
Hydrozirconation/transmetalation of acetylenic stannanes. New 1,1-dimetallo reagents
作者:Bruce H. Lipshutz、Robert Keil
DOI:10.1016/0020-1693(94)03852-x
日期:1994.6
substituted by both Bu3Sn and Cp2ZrCI groups on the terminal sp2-1ike carbon. These stereodefined reagents can be selectively transmetalated at zirconium to afford cuprates which deliver product vinyl stannanes in both substitution and Michael addition reactions.
Total synthesis of the cytotoxic Annonaceous acetogenin (30S)-bullanin
作者:James A. Marshall、Kevin W. Hinkle
DOI:10.1016/s0040-4039(97)10739-0
日期:1998.3
The totalsynthesis of (+)-(30S)-bullanin, a highly cytotoxic annonaceousacetogenin, was effected by a convergent approach in which the key core bis-2,2′-tetrahydrofuran stereocenters were introduced through a combination of Sharpless asymmetric dihydroxylation and SE2′ additions of oxygenated nonracemic allylic stannane and indium reagents to γ-oxygenated aldehydes.
(+)-(30S)-bullanin(一种具有高细胞毒性的非乙酰乙酸原)的总合成是通过一种收敛方法实现的,该方法通过结合Sharpless不对称二羟基化反应和结合引入关键核心bis -2,2'-四氢呋喃立体中心。 S E 2'向γ-氧化的醛中添加氧化的非外消旋烯丙基锡和铟试剂。
Palladium-catalyzed synthesis of 2-substituted indoles