SAR of 2-benzyl-4-aminopiperidines NK1 antagonists. Part 21. synthesis of CGP 49823
摘要:
CGP 49823 is a potent NK1 antagonist which is centrally active after oral administration. The SAR of the C-2 substituent was investigated with respect to the affinity to the NK1 receptor. A practical synthesis of CGP 49823, suitable for scale-up, was developed. The key-step, a tandem acyliminium ion cyclization / Ritter reaction, gave trans 2-benzyl-4-acetamido-piperidines with high diastereoselectivity. Copyright (C) 1996 Elsevier Science Ltd
A detailed investigation of the aza-Prins reaction
作者:Adrian P. Dobbs、Sebastien J. J. Guesné、Robert J. Parker、John Skidmore、Richard A. Stephenson、Mike B. Hursthouse
DOI:10.1039/b915797b
日期:——
The development of a Lewis acid-promoted aza-Prins reaction to form piperidines and pyrrolidines is described. Indium trichloride has been found to be a highly successful and mild Lewis acid for promoting this reaction. A thorough mechanistic investigation is described, including the factors that influence the formation of the 5- or 6-membered ring product(s).
Re2O7-catalyzed three-component synthesis of protected secondary and tertiary homoallylic amines
作者:Suman Pramanik、Prasanta Ghorai
DOI:10.1039/c2cc15472b
日期:——
Three-componentsynthesis of protected secondary and "for the first time" tertiary homoallylic amines is achieved from carbonyl, carbamate, and allyltrimethylsilanes using a Re(2)O(7)-catalyst under mild and open flask conditions. Excellent chemoselectivities and diastereoselectivities were observed.
Bismuth Triflate-Catalyzed Addition of Allylsilanes to N-Alkoxycarbonylamino Sulfones: Convenient Access to 3-Cbz-Protected Cyclohexenylamines
作者:Thierry Ollevier、Zhiya Li
DOI:10.1002/adsc.200900710
日期:2009.12
Bismuth triflate was found to be an efficient catalyst in the Sakurai reaction of allyltrimethylsilanes with N-alkoxycarbonylaminosulfones. The reaction proceeded smoothly with a low catalyst loading of Bi(OTf)3⋅4 H2O (2–5 mol%) to afford the corresponding protected homoallylic amines in very good yields (up to 96%). A sequential allylation reaction followed by ring-closing metathesis delivers 6–8
Iodine as a Very Powerful Catalyst for Three-Component Synthesis of Protected Homoallylic Amines
作者:Prodeep Phukan
DOI:10.1021/jo0498462
日期:2004.5.1
Iodine catalyzes efficiently the three-component condensation of aldehydes, benzyl carbamate, and allyltrimethylsilane to afford the corresponding protectedhomoallylic amines in excellent yields.
The first catalytic Sakurai reaction of N-alkoxycarbonylamino sulfones with allyltrimethylsilane
作者:Thierry Ollevier、Zhiya Li
DOI:10.1039/b613331b
日期:——
We report the firstcatalytic Sakurai reaction of N-alkoxycarbonylamino sulfones with allylsilanes. The allylation reaction of N-alkoxycarbonylamino phenylsulfones with allyltrimethylsilane proceeded smoothly with low catalyst loading of bismuth triflate (2.0 mol%) to afford the corresponding protected homoallylic amines in moderate to very good yields (up to 96%).