117654-86-1Relevant articles and documents
[Co(TPP)]-Catalyzed Formation of Substituted Piperidines
Lankelma, Marianne,Olivares, Astrid M.,de Bruin, Bas
supporting information, p. 5658 - 5663 (2019/04/08)
Radical cyclization via cobalt(III)-carbene radical intermediates is a powerful method for the synthesis of (hetero)cyclic structures. Building on the recently reported synthesis of five-membered N-heterocyclic pyrrolidines catalyzed by CoII porphyrins, the [Co(TPP)]-catalyzed formation of useful six-membered N-heterocyclic piperidines directly from linear aldehydes is presented herein. The piperidines were obtained in overall high yields, with linear alkenes being formed as side products in small amounts. A DFT study was performed to gain a deeper mechanistic understanding of the cobalt(II)-porphyrin-catalyzed formation of pyrrolidines, piperidines, and linear alkenes. The calculations showed that the alkenes are unlikely to be formed through an expected 1,2-hydrogen-atom transfer to the carbene carbon. Instead, the calculations were consistent with a pathway involving benzyl-radical formation followed by radical-rebound ring closure to form the piperidines. Competitive 1,5-hydrogen-atom transfer from the β-position to the benzyl radical explained the formation of linear alkenes as side products.
Somatostatin analogue compounds
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Page 18, (2010/11/30)
Compounds having somatostatin activity of the following Formula I, 1wherein, R1 is aryl, substituted-aryl, and aryl-(lower-alkyl)-; R2 is lower alkyl, amino substituted lower alkyl, -carboxy-(lower-alkyl), -carbamic acid-(lower-alkyl) and -carboxy-(lower-alkyl)-aryl; and R3 and R4 are independently, lower-alkyl, aryl, substituted-aryl, (substituted-aryl)-(lower-alkyl)-, heteroaryl, (heteroaryl)-(lower-alkyl)-, substituted-heteroaryl, (substituted heteroaryl)-(lower-alkyl)-, heterocyclic, heterocyclic-(lower-alkyl)-, substituted-heterocyclic, (substituted-heterocylic)-(lower alkyl)-, -carboxy-(lower-alkyl), and -carboxy-(lower-alkyl)-aryl; or a pharmaceutically acceptable, ester, ether, or salt thereof; methods for their use; and preparation.
Diastereoselectivity in the cyclization of alkene radical cations generated under non-oxidizing conditions: Contact ion pairs and memory effects
Crich, David,Ranganathan, Krishnakumar
, p. 12422 - 12423 (2007/10/03)
A series of highly diastereomerically enriched 1,5-dimethyl-, 2,5-dimethyl-, and 3,5-dimethyl-N-benzyl-5-nitro-4-(diphenylphosphatoxy)hexylamines were exposed to tributyltin hydride and AIBN in benzene at reflux. The ensuing reactions, interpreted in term
