Heterobimetallic Control of Regioselectivity in Alkyne Hydrostannylation: Divergent Syntheses of α- and (<i>E</i>)<i>-</i>β<i>-</i>Vinylstannanes via Cooperative Sn–H Bond Activation
作者:Li-Jie Cheng、Neal P. Mankad
DOI:10.1021/jacs.9b00068
日期:2019.2.27
terminal alkynesunder mild conditions, with Markovnikov/anti-Markovnikov selectivity controlled by the Cu/M pairing. By using the MeIMesCu-FeCp(CO)2 catalyst, a variety of α-vinylstannanes were produced from simple alkyl-substituted alkynes and Bu3SnH in high yield and good regioselectivity; these products are challenging to access under mononuclear metal-catalyzed hydrostannylation conditions. In addition
Molecular hydrogen adds to aliphatic and aromatic alkynylstannanes in the presence of a ruthenium catalyst, pushing the stannyl group to the adjacent carbon atom to give alpha-substituted vinylstannanes. This is the first achievement of hydrogenation of alkynylstannanes, which is applicable also to the deuteration affording precursors for an important class of deuterium-labeled compounds.
Iron-Catalyzed Regiodivergent Hydrostannation of Alkynes: Intermediacy of Fe(IV)–H versus Fe(II)–Vinylidene
作者:Jianguo Liu、Heng Song、Tianlin Wang、Jiong Jia、Qing-Xiao Tong、Chen-Ho Tung、Wenguang Wang
DOI:10.1021/jacs.0c11448
日期:2021.1.13
iron-aryloxide catalyst (2, X = O-, R = Cy) affords an iron(II) vinylidene intermediate, allowing for gem-addition of the Sn-H to the terminal-carbon producing β-vinylstannanes. These catalytic reactions exhibit excellent regioselectivity and broad functional group compatibility and enable the large-scale synthesis of diverse vinylstannanes. Many new reactions have been established based on such a synthetic
我们报告了一种铁系统 Cp*Fe(1,2-R2PC6H4X),它通过调节离子金属-杂原子键 (Fe-X) 的反应性来控制炔烃的马尔科夫尼科夫和反马尔科夫尼科夫氢氢化。将 nBu3SnH 依次添加到铁-酰胺基催化剂 (1, X = HN-, R = Ph) 中提供了二锡基 Fe(IV)-H 物种,负责跨 C≡C 键的 Sn-H 键的顺式加成生产支链α-乙烯基锡烷。通过芳基氧化铁催化剂 (2, X = O-, R = Cy) 活化炔烃的 C(sp)-H 键,得到亚乙烯基铁 (II) 中间体,允许 Sn-H 与产生β-乙烯基锡烷的末端碳。这些催化反应表现出优异的区域选择性和广泛的官能团兼容性,能够大规模合成多种乙烯基锡烷。
Catalytic, Enantioselective Synthesis of Polycyclic Nitrogen, Oxygen, and Sulfur Heterocycles via Rh-Catalyzed Alkene Hydroacylation
作者:Kevin L. Vickerman、Levi M. Stanley
DOI:10.1021/acs.orglett.7b02230
日期:2017.10.6
Enantioselective synthesis of polycyclic nitrogen, oxygen, and sulfur heterocycles by rhodium-catalyzed intramolecular alkene hydroacylation is reported. The intramolecular hydroacylation reactions generate 1,4-dihydrocyclopenta[b]indol-3(2H)-ones and 3,4-dihydrocyclopenta[b]indol-1(2H)-one in moderate-to-high yields (65–99%) with good-to-excellent enantioselectivities (84–99% ee). The catalyst system
据报道,通过铑催化的分子内烯烃加氢酰化反应可对映选择性地合成多环氮,氧和硫杂环。分子内加氢酰化反应生成1,4-二氢环戊二烯并[ b ]吲哚-3-(2 ħ) -酮和3,4-二氢环戊二烯并[ b ]吲哚-1-(2- ħ) -酮在中度到高的产率(65-70 99%)具有良好至优异的对映选择性(84–99%ee)。该催化剂体系还促进3-乙烯基呋喃-,3-乙烯基苯并噻吩-和3-乙烯基噻吩-2-甲醛的烯烃加氢酰化反应,以中等至高的收率(71-91%的收率)产生相应的酮产物,并具有出色的对映选择性( 97–99%ee)。