A stannous chloride-induced deacetalisation–cyclisation process to prepare the ABC ring system of 'upenamide
摘要:
A stannous chloride-induced deacetalisation-cyclisation approach to the ABC core of the macrocyclic alkaloid, 'upenamide is reported. The use of a substituted beta-lactone to prepare a C-2 substituted 'upenamide analogue is also disclosed. (C) 2004 Elsevier Ltd. All rights reserved.
Reductive Amination of Aldehydes and Ketones with Sodium Triacetoxyborohydride. Studies on Direct and Indirect Reductive Amination Procedures<sup>1</sup>
作者:Ahmed F. Abdel-Magid、Kenneth G. Carson、Bruce D. Harris、Cynthia A. Maryanoff、Rekha D. Shah
DOI:10.1021/jo960057x
日期:1996.1.1
triacetoxyborohydride is presented as a general reducing agent for the reductiveamination of aldehydes and ketones. Procedures for using this mild and selective reagent have been developed for a wide variety of substrates. The scope of the reaction includes aliphatic acyclic and cyclic ketones, aliphatic and aromatic aldehydes, and primary and secondary amines including a variety of weakly basic and
Direct transferhydrogenation of imines was observed with ammonia–borane, which proceeded under mild conditions without the help of a catalyst. The results of deuterium kinetic isotope effects, Hammett correlations, and DFT calculations all support a concerted double‐hydrogen‐transfer mechanism (see scheme).
With 2-(trimethylsilyl)aryl triflates as aryne precursors, an unprecedented three-component carboarylation reaction of unactivated imines with arynes and carbon nucleophiles has been developed to access a variety of functionalized tertiaryamines...
Metalation of diazines XVII Very hindered bases as new metalating agents, Improvement of regioselectivity for the metalation of 3-chloro-6-methoxypyridazine
The different factors governing the regioselectivity of the metalation of 3-chloro-6-methoxypyridazine with alkylamides were studied. Very hindered bases were used as new metalating agents and a very good regioselectivity was obtained.
with nonpolar alkenes and polar imines. Upon treatment with one equiv. of borate reagent B(C6F5)3 or [Ph3C][B(C6F5)4], complex NP1-Sc can act as an efficient catalyst for ortho-C–H alkylation of pyridines towards alkenes. In the presence of 1:1 mixed secondary amine of HN (SiMe3)2 and HNBn2, complex NP2-Gd can catalyze ortho-C–H addition of pyridines towards imines, effectively. A wide range of substrates