hydroformylation and hydroaminomethylation of α-substituted acrylamides is described using 1,3-phosphite-phosphoramidite ligands based on a sugar backbone. A broad scope of chiral aldehydes and amines were afforded in high yields and excellent enantioselectivities (up to 99%). Furthermore, the synthetic potential of this method is demonstrated by the single-step synthesis of the brain imaging molecule RWAY.
Asymmetric synthesis of β2-amino acids: 2-substituted-3-aminopropanoic acids from N-acryloyl SuperQuat derivatives
作者:James E. Beddow、Stephen G. Davies、Kenneth B. Ling、Paul M. Roberts、Angela J. Russell、Andrew D. Smith、James E. Thomson
DOI:10.1039/b707689d
日期:——
Conjugateaddition of lithium dibenzylamide to (S)-N(3)-acryloyl-4-isopropyl-5,5-dimethyloxazolidin-2-one (derivedfrom l-valine) and alkylation of the resultant lithium beta-amino enolate provides, after deprotection, a range of (S)-2-alkyl-3-aminopropanoic acids in good yield and high ee. Alternatively, via a complementary pathway, conjugateaddition of a range of secondary lithium amides to (S)
Nickel-Catalyzed Intramolecular Arylcyanation for the Synthesis of 3,3-Disubstituted Oxindoles
作者:Andy Yen、Mark Lautens
DOI:10.1021/acs.orglett.8b01772
日期:2018.7.20
A nickel-catalyzed arylcyanation reaction for the synthesis of 3,3-disubstitutedoxindoles has been developed. This method features a bench-stable precatalyst system and serves as an economical alternative to the existing palladium-catalyzed arylcyanations described to date. A wide scope of oxindole products were accessible in moderate to good yields, and the rich chemistry of the newly installed nitrile
Radical Annulation of 2-Cyanoaryl Acrylamides via C═C Double Bond Cleavage: Access to Amino-Substituted 2-Quinolones
作者:Wen-Jin Xia、Tai-Gang Fan、Zhi-Wei Zhao、Xin Chen、Xiang-Xiang Wang、Ya-Min Li
DOI:10.1021/acs.orglett.1c02281
日期:2021.8.6
2-cyanoaryl acrylamides via C═C double bond cleavage has been developed for facile and efficient access to a broad spectrum of functionalized 4-amino-2-quinolones, which are important N-heterocycles. In this transformation, the solvent THF is demonstrated to play a crucial role, and the addition of alkyl radicals to nitrile, 1,5-hydride shift, and cleavage of the C–C bond are involved in the mechanism
作者:Hongmiao Wu、Bin Yang、Lin Zhu、Ronghua Lu、Guigen Li、Hongjian Lu
DOI:10.1021/acs.orglett.6b02706
日期:2016.11.18
An oxy-palladation, formal Wagner–Meerwein rearrangement and fluorination cascade has been established for generating fluorinated oxazolidine-2,4-diones and oxazolidin-2-ones. The reaction has a broad substrate scope in which both aryl and alkyl groups can be utilized as efficient migrating groups. Experimental evidence suggests that the reaction is initiated by anti-oxy-palladation of the olefin,