Improved synthesis of quinine alkaloids with the Teoc protective group
摘要:
TeocCl (Teoc: C(=O)O(CH2)(2)TMS) generated in situ was conveniently used for trans-protection of the N-Bn piperidine intermediate to N-Teoc piperidine. Later, deprotection of the Teoc group and the subsequent quinuclidine ring formation was achieved with CsF in a domino fashion to afford the quinine alkaloids. (c) 2005 Elsevier Ltd. All rights reserved.
ESI-MS spectral methods. Further, structures of two of the complexes have been determined by single crystal X-ray diffraction technique which revealed a pseudo octahedral geometry with the coordination of the quinoline nitrogen and quinoline oxygen atoms of the ligand. All the newcomplexes have been employed as efficient catalysts in N-alkylation reactions for the synthesis of tertiary amines by the coupling
一系列新的通式为[RuH(CO)(EPh 3)2 L](1-6)的8-羟基喹啉-2-羧醛的Ru(II)配合物(E = P或As,L = N '-(((8-羟基喹啉-2-基)亚甲基)噻吩-2-碳酰肼(HQ-THy),N'-(((8-羟基喹啉-2-基)亚甲基)异烟酰肼(HQ-IHy),N'-已经合成了((8-羟基喹啉-2-基)亚甲基)苯甲酰肼(HQ-BHy)。它们已通过元素分析,IR,NMR(1 H,13 C和31P)和ESI-MS光谱方法。此外,已经通过单晶X射线衍射技术确定了两种配合物的结构,该技术揭示了配体的喹啉氮和喹啉氧原子配位的伪八面体几何形状。通过将仲胺与芳族伯醇在低催化剂负载下以最大收率偶联,所有新的络合物已被用作N-烷基化反应中合成叔胺的有效催化剂。另外,已经充分研究了取代基对配体,不同溶剂以及碱和催化剂负载量对配合物催化活性的影响。综合大楼1业已发现,AlO3是醇与胺的N-烷
Half-sandwich ruthenium-carbene catalysts: Synthesis, characterization, and catalytic application in the N-alkylation of amines with alcohols
作者:Murat Kaloğlu
DOI:10.1016/j.ica.2019.119163
日期:2019.12
the synthesis and characterization of new half-sandwich ruthenium complexes containing oxygen functionalised N-aryl and N-alkyl benzimidazol-2-ylidene ligands have been reported. All ruthenium complexes were tested as catalysts for a wide range of substrates in the N-alkylation of secondary cyclic amines such as pyrrolidine and piperidine, and 4-methylaniline which was a primary aromaticamine with
A hydrogen borrowing annulation strategy for the stereocontrolled synthesis of saturated aza-heterocycles
作者:Anna E. R. Chamberlain、Kieran J. Paterson、Roly J. Armstrong、Heather C. Twin、Timothy J. Donohoe
DOI:10.1039/d0cc00903b
日期:——
A hydrogen borrowing annulation strategy enables the stereocontrolled synthesis of C2, C3 and C4-substituted saturated aza-heterocycles.
一种氢借位缩合策略实现了C2、C3和C4取代饱和氮杂环的立体控制合成。
Ruthenium-Catalyzed Cascade N- and C(3)-Dialkylation of Cyclic Amines with Alcohols Involving Hydrogen Autotransfer Processes
作者:Basker Sundararaju、Zhou Tang、Mathieu Achard、Gangavaram V. M. Sharma、Loïc Toupet、Christian Bruneau
DOI:10.1002/adsc.201000546
日期:2010.12.17
An unprecented N- and C(3)-dialkylation of unactivated amines by a cascade reaction via borrowing hydrogen methodology using new (arene)ruthenium(II) complexes featuring phosphinosulfonate ligands is described. This reaction is highly regioselective and produces water as the only side product.