128372-78-1Relevant academic research and scientific papers
Highly Enantioselective Synthesis of Chiral γ-Lactams by Rh-Catalyzed Asymmetric Hydrogenation
Lang, Qiwei,Gu, Guoxian,Cheng, Yaoti,Yin, Qin,Zhang, Xumu
, p. 4824 - 4828 (2018/06/08)
A Rh/bisphosphine-thiourea (ZhaoPhos) catalytic system has been identified for the straightforward asymmetric synthesis of chiral γ-lactams. A variety of NH free α,β-unsaturated lactams bearing a β-aryl or β-alkyl substituent were smoothly hydrogenated to
Rh-IndOlefOx catalyzed conjugate addition/Heck-type coupling of organoboronics to a lactam or a lactone
Kuuloja, Noora,Vaismaa, Matti,Franzén, Robert
supporting information; experimental part, p. 2313 - 2318 (2012/04/04)
Four indole-olefin-oxazoline (IndOlefOx) ligands were synthesized and evaluated in Rh-catalyzed reactions between organoboronics and a lactam or a lactone. In addition to the expected conjugate addition products, the formation of significant amounts of Heck-type products was observed. The scope and limitations of these reactions were investigated.
Asymmetric synthesis of β-substituted γ-lactams via rhodium/diene-catalyzed 1,4-additions: Application to the synthesis of (R)-baclofen and (R)-rolipram
Shao, Cheng,Yu, Hong-Jie,Wu, Nuo-Yi,Tian, Ping,Wang, Rui,Feng, Chen-Guo,Lin, Guo-Qiang
supporting information; experimental part, p. 788 - 791 (2011/04/16)
An efficient rhodium/diene-catalyzed asymmetric addition of arylboronic acids to α,β-unsaturated γ-lactams has been developed. The power of this methodology is further demonstrated by the concise synthesis of (R)-baclofen and (R)-rolipram.
The Synthesis of Aracemic 4-Substituted Pyrrolidinones and 3-Substituted Pyrrolidines. An Asymmetric Synthesis of (-)-Rolipram
Meyers, A. I.,Snyder, Lawrence
, p. 36 - 42 (2007/10/02)
Conjugate additions of RCuCNLi to the chiral α,β-unsaturated lactam 4 gives almost exclusive exo addition - a reversal in stereochemistry when cuprates were added to chiral lactam 1.The lactams 5 were transformed into 4-substituted pyrrolidinones 8 via a three-step sequence which involved decarbalkoxylation, silane reduction and metal-ammonia benzylamine cleavage.The chemical yields as well as the enantiomeric purity were very high for this process.As an example of the usefulness of this scheme, the antidepressant (-)-Rolipram was prepared in good overall yield.Furthermore, the bicyclic lactams 6 were readily transformed, using alane as the reducing agent, to 3-substituted pyrrolidines 11.Absolute configurations of 8 and 11 were confirmed by comparison with literature assignments which also gave strong support to the facial addition of the cuprates to 4.
Resolution of 4-phenyl-2-pyrrolidinone: A versatile synthetic intermediate
Zelle
, p. 1023 - 1026 (2007/10/02)
A resolution of 4-phenyl-2-pyrrolidinone is described. The resulting enantiomerically pure pyrrolidinones are exploited as precursor to 3-phenylpyrrolidines and 3-phenyl-γ-amino acids (4-amino-3-phenylbutanoic acid derivatives).
