Pd/C-Catalyzed Alkylation of Heterocyclic Nucleophiles with Alcohols through the “Borrowing Hydrogen” Process
作者:Anggi Eka Putra、Yohei Oe、Tetsuo Ohta
DOI:10.1002/ejoc.201501030
日期:2015.12
The alkylation of heterocyclic compounds is important for the synthesis of various biologically active compounds. In this paper, we present the development of a Pd/C-catalyzedalkylation of heterocyclic compounds using alcohols as the alkylating agents. This method gives the corresponding alkylated heterocyclic compounds in high yields (up to 99 %). The commercially available catalyst can be recovered
Iron‐Catalyzed Borrowing Hydrogen
<i>C</i>
‐Alkylation of Oxindoles with Alcohols
作者:Mubarak B. Dambatta、Kurt Polidano、Alexander D. Northey、Jonathan M. J. Williams、Louis C. Morrill
DOI:10.1002/cssc.201900799
日期:——
general and efficient iron‐catalyzed C‐alkylation of oxindoles has been developed. This borrowing hydrogen approach employing a (cyclopentadienone)iron carbonyl complex (2 mol %) exhibited a broad reaction scope, allowing benzylic and simple primary and secondary aliphatic alcohols to be employed as alkylating agents. A variety of oxindoles underwent selective mono‐C3‐alkylation in good‐to‐excellent
A direct catalytic asymmetricaldol‐type reaction of 3‐substituted‐2‐oxindoles with glyoxal derivatives and ethyl trifluoropyruvate, catalyzed by a chiral N,N′‐dioxide–Sc(OTf)3 (Tf=trifluoromethanesulfonyl) complex, has been developed that tolerates a wide range of substrates. The reaction proceeds in good yields and excellent enantioselectivities (up to 93 % yield, 99:1 diastereomeric ratio (dr),
Sc takes action: The highly enantioselectivehydroxyaminationreaction of N‐unprotected 2‐oxindoles with nitrosoarenes has been realized using the Sc(OTf)3/L1 complex. The catalyst system exhibited remarkably broad substrate scope and high efficiency. This transformation is the first example of a chiral ScIII/enolate activating a nitrosoarene, and can be conducted on a gram scale without loss in the
Sc发挥作用:使用Sc(OTf)3 / L1络合物实现了N-未保护的2-氧吲哚与亚硝基芳烃的高度对映选择性羟基胺化反应。该催化剂体系表现出显着的底物范围和高效率。该转化是手性Sc III /烯酸酯活化亚硝基芳烃的第一个实例,并且可以以克级进行,而不会损失ee 值。
Highly Enantioselective Synthesis of 3-Amino-2-oxindole Derivatives: Catalytic Asymmetric α-Amination of 3-Substituted 2-Oxindoles with a Chiral Scandium Complex
A highly enantioselective α‐amination of 3‐substitutedoxindoles with azodicarboxylates catalyzed by a chiral Sc(OTf)3/N,N′‐dioxide complex (Tf: triflate) has been developed and affords the corresponding 3‐amino‐2‐oxindole derivatives in high yields (up to 98 %) with excellent enantioselectivities (up to 99 % ee). The procedure is capable of tolerating a relatively wide range of substrates, and excellent