Isatin Ketimines Research Articles

ChemInform Abstract: Diastereoselective Construction of 3‐Aminooxindoles with Adjacent Stereocenters: Stereocontrolled Addition of γ‐Substituted Allylindiums to Isatin Ketimines.

AbstractAn indium‐mediated Barbier‐type C—C bond formation is achieved by addition of γ‐substituted allylic reagents to the C=N bond of isatin ketimines, resulting in the formation of 3‐allyl‐3‐aminooxindoles with a high degree of stereocontrol and without hydrolysis of the isatin ketimines.

A Journey in the Catalytic Synthesis of 3-Substituted 3-Amino­oxindoles

3-Substituted 3-aminooxindoles represent a type of privileged scaffold widely present in natural products and pharmaceutically active compounds. Thus, their efficient construction is of current interest. This account describes our efforts in the development of new strategies and reactions for facile access to this prominent framework. 1 Introduction 2 Nucleophilic Addition to Isatin Ketimines 3 Direct Amination of 3-Substituted Oxindoles 4 Substitution Reactions of 3-Hydroxyoxindoles 5 Conclusion and Outlook

Diastereoselective Construction of 3‐Aminooxindoles with Adjacent Stereocenters: Stereocontrolled Addition of γ‐Substituted Allylindiums to Isatin Ketimines

AbstractThe diastereoselective construction of 3‐allyl‐3‐aminooxindoles that have two adjacent stereocenters has been achieved by the In‐promoted Barbier‐type addition of γ‐substituted allylic halides to the C=N bond of isatin ketimines. The reactions of cinnamyl‐, crotyl‐, and geranylindium compounds with isatin ketimines proceeded in either aqueous or alcohol solution. The addition of a cyclohexenylindium species to an isatin ketimine was carried out in N,N‐dimethylformamide (DMF), and the addition of ethyl 4‐bromocrotonate to an isatin ketimine in EtOH gave oxindole‐based β‐amino acid scaffolds. In all of these processes, the reaction conditions were screened to obtain the respective 3‐allyl‐3‐aminooxindoles with very high stereoselectivity. In addition, plausible TS models are proposed, and representative synthetic transformations were carried out by using the oxindole‐based β‐amino acid scaffolds. Furthermore, the stereochemistry of representative compounds were unequivocally established by single‐crystal X‐ray structure analysis.

Cinchona alkaloid thiourea mediated asymmetric Mannich reaction of isocyanoacetates with isatin-derived ketimines and subsequent cyclization: enantioselective synthesis of spirooxindole imidazolines

The organocatalyzed asymmetric Mannich reaction of isocyanoacetates with isatin ketimines and subsequent cyclization were developed, leading to spirooxindole imidazolines in high yields and excellent stereoselectivities.

A highly efficient Mukaiyama-Mannich reaction of N-Boc isatin ketimines and other active cyclic ketimines using difluoroenol silyl ethers catalyzed by Ph3PAuOTf.

Ph3PAuOTf is identified as a powerful catalyst for the addition of difluoroenol silyl ethers to N-Boc isatin ketimines and other two kinds of active cyclic ketimines. This represents the first Au(i)-catalyzed Mukaiyama-Mannich reaction, and the corresponding non-fluorinated enol silyl ether proves to be even much more reactive under the same conditions. This method paves the way to the total synthesis of difluoromethylated analogues of AG-041R, a gastrin/CCK-B receptor antagonist.

Enantioselective aza-Morita-Baylis-Hillman reaction between acrylates and N-Boc isatin ketimines: asymmetric construction of chiral 3-substituted-3-aminooxindoles.

The first enantioselective aza-Morita–Baylis–Hillman reaction of acrylates with ketimines derived from isatins has been developed. With 2 mol% of chiral bifunctional phosphine-squaramide 4e, optically active 3-substituted-3-amino-2-oxindoles were obtained in excellent yields with up to 91% ee.

Highly Enantioselective Organocatalytic aza-Henry Reaction of Nitroalkanes to N-Boc Isatin Ketimines

研究实现了高对映选择性的硝基烷烃对N-Boc靛红亚胺1的不对称aza-Henry反应,来构建胺基季碳氧化吲哚.发现在金鸡纳碱衍生的叔胺-酚羟基双功能催化剂C5的作用下,10种不同取代的N-Boc靛红亚胺与硝基甲烷的反应均能顺利进行,以66%~91%的对映选择性得到目标产物,产物的绝对构型通过X-ray单晶衍射加以确定.硝基乙烷和硝基丙烷也能高对映选择性地参与反应,但非对映选择性不佳.