Highly Regio- and Enantioselective Reductive Coupling of Alkynes and Aldehydes via Photoredox Cobalt Dual Catalysis
作者:Yan-Lin Li、Shi-Qi Zhang、Jie Chen、Ji-Bao Xia
DOI:10.1021/jacs.1c03527
日期:2021.5.19
A Co-catalyzed highly regio- and enantioselective reductive coupling of alkynes and aldehydes has been developed under visible light photoredox dual catalysis. A variety of enantioenriched allylic alcohols have been obtained by using unsymmetrical internal alkynes and commercially available catalyst, chiral ligand, and reagents. It is noteworthy that this approach has considerable advantages, such
在可见光光氧化还原双催化下开发了一种共催化的炔烃和醛的高度区域选择性和对映选择性还原偶联。通过使用不对称内部炔烃和市售催化剂、手性配体和试剂,已经获得了多种对映体富集的烯丙醇。值得注意的是,这种方法具有相当大的优势,例如出色的区域-(> 40 个示例> 95:5)、立体-(高达> 95:5 E / Z)和对映选择性(92-99% ee,> 35个例子)控制,反应条件温和,底物范围广,官能团相容性好,使其对映选择性炔-醛还原偶联反应有了很大的改进。
Nickel-Catalyzed Enantioselective Alkylative Coupling of Alkynes and Aldehydes: Synthesis of Chiral Allylic Alcohols with Tetrasubstituted Olefins
A highly efficient nickel-catalyzed asymmetric alkylative coupling of alkynes, aldehydes, and dimethylzinc has been realized by using bulky spirobiindane phosphoramidite ligands, affording allylicalcohols with a tetrasubstituted olefin functionality in high yields, high regioselectivities, and excellent enantioselectivities.
Alkynes as Allylmetal Equivalents in Redox-Triggered C–C Couplings to Primary Alcohols: (<i>Z</i>)-Homoallylic Alcohols via Ruthenium-Catalyzed Propargyl C–H Oxidative Addition
作者:Boyoung Y. Park、Khoa D. Nguyen、Mani Raj Chaulagain、Venukrishnan Komanduri、Michael J. Krische
DOI:10.1021/ja505962w
日期:2014.8.27
The cationic ruthenium catalyst generated upon the acid–base reaction of H2Ru(CO)(PPh3)3 and 2,4,6-(2-Pr)3PhSO3H promotes the redox-triggered C–C coupling of 2-alkynes and primaryalcohols to form (Z)-homoallylic alcohols with good to complete control of olefin geometry. Deuterium labeling studies, which reveal roughly equal isotopic compositions at the allylic and distal vinylic positions, along with
deoxygenative homocoupling reaction of the allyl alcohol to give the corresponding 1,5-diene as a major product. In addition to the deoxygenative homocoupling product, the allyl amine into which aniline was introduced was also obtained by using 1,2-diphenylhydrazine in the reaction of 1,3-diphenyl-2-methylprop-2-en-1-ol. Oxovanadium(V)-catalyzed deoxygenative homocoupling reaction of benzyl alcohols could
Asymmetric Hydrogenation of Allylic Alcohols Using Ir–N,P-Complexes
作者:Jia-Qi Li、Jianguo Liu、Suppachai Krajangsri、Napasawan Chumnanvej、Thishana Singh、Pher G. Andersson
DOI:10.1021/acscatal.6b02456
日期:2016.12.2
γ-disubstituted and β,γ-disubstituted allylicalcohols were prepared and successfully hydrogenated using suitable N,P-based Ir complexes. High yields and excellent enantioselectivities were obtained for most of the substrates studied. This investigation also revealed the effect of the acidity of the N,P–Ir-complexes on the acid-sensitive allylicalcohols. DFT ΔpKa calculations were used to explain the effect of