Palladium-Catalyzed Enantioselective Domino Heck–Cyanation Sequence: Development and Application to the Total Synthesis of Esermethole and Physostigmine
An efficient synthesis of functionalized 3-alkyl-3-cyanomethyl-2-oxindole 1 by a palladium-catalyzed domino Heck-cyanation reaction has been developed. Reaction of ortho-iodoanilide 5 with potassium ferro(II)cyanide, K(4)[Fe(CN)(6)], dissolved in DMF in the presence of palladium acetate and sodium carbonate afforded oxindole 1 in good to excellent yields. An enantioselective domino Heck-cyanation process
A catalytic enantioselective domino Heck carbonylation reaction of o-iodoacrylanilides with phenylacetylenes or water has been developed using a Pd/(Cu) catalytic system containing a chiral diphosphine ligand L9, furnishing a wide array of chiral β-carbonylated 3,3-disubstituted oxindoles in high yields with up to 99 % ee values.
The first Pd‐catalyzed domino Heck/phosphorylation of N‐(2‐iodophenyl)acrylamides with secondary phosphine oxides has been developed. The use of PdCl2 as a catalyst, 1,4‐bis(diphenylphosphino)butane as a ligand, K2CO3 as a base, various N‐(2‐iodophenyl)acrylamide derivatives are tolerant in this transformation, affording 3‐phosphinomethyl 3,3‐disubstituted oxindole products in good to excellent yields
N-(2-碘苯基)丙烯酰胺与仲膦氧化物的第一个Pd催化的多米诺Heck /磷酸化反应已经开发出来。在此转化过程中可以耐受使用PdCl 2作为催化剂,1,4-双(二苯基膦基)丁烷作为配体,K 2 CO 3作为碱,各种N-(2-碘苯基)丙烯酰胺衍生物,从而获得3-膦基甲基3,3-二取代的羟吲哚产品,收率良好至优异。这一转变为一步一步形成新的C-C和P-C键,羟吲哚环提供了一条直接途径。而且,该方法可轻松适用于大规模制备。
Synthesis of Diversely Functionalized Oxindoles Enabled by Migratory Insertion of Isocyanide to a Transient σ-Alkylpalladium(II) Complex
作者:Wangqing Kong、Qian Wang、Jieping Zhu
DOI:10.1002/anie.201603950
日期:2016.8.8
Palladium‐catalyzed intramolecular carbopalladation of N‐aryl acrylamides followed by migratory insertion of an isocyanide‐coordinated C(sp3)−Pd intermediate afforded an alkylimidoyl−PdII complex, which can be intercepted by a nucleophile, including heteroarenes. In addition to amides, the alkylimidoyl−PdII complex was successfully converted into esters, ketones, and bis‐heterocyclic compounds. An
A Ni/(S,S)-BDPP-catalyzed intramolecular Heck cyclization of N-(2-iodo-aryl) acrylamide with 2-methyl-2-phenylmalononitrile was developed to give oxindoles with good enantioselectivities. We found that utilizing such an electrophilic cyanation reagent could tackle the deleterious effect of the coordinative cyanide ion in the asymmetric alkene arylcyanation.
开发了 Ni/( S , S )-BDPP 催化的N -(2-碘代芳基) 丙烯酰胺与 2-甲基-2-苯基丙二腈的分子内 Heck 环化反应,得到具有良好对映选择性的羟吲哚。我们发现使用这种亲电子氰化试剂可以解决配位氰化物离子在不对称烯烃芳基氰化中的有害影响。