87338-11-2Relevant academic research and scientific papers
Synthesis of Aza Macrocycles by Nucleophilic Ring Closure with Cesium Tosylamides
Vriesema, Bindert K.,Buter, Jan,Kellogg, Richard M.
, p. 110 - 113 (2007/10/02)
Long-chain diamines as their bis tosylamide derivatives are deprotonated by Cs2CO3 in dimethylformamide solution to give the dicesium salts.These react smoothly with various dibromides or dimesylates to afford the cyclic diamines as their tosyl derivatives.The yields, depending on the size of the ring, range between 25percent and 95percent of isolated product.The largest ring made, 1,12-diazaoctacosane (as the tosylamide derivative) was isolated in 60percent yield.The tosyl groups are readily removed with sodium amalgam in Na2HPO4-buffered methanolic solution.Chiral macrocyclic amines have also been prepared by using this cesium salt method.
RING-CLOSURE REACTIONS. XX. AN EFFICIENT SYNTHESIS OF MANY-MEMBERED AZACYCLOALKANES
Gargano, Patrizia,Mandolini, Luigi
, p. 31 - 34 (2007/10/02)
An efficient cyclization of N-tosyl-ω-bromoalkylamines to N-tosylazacycloalkanes in the presence of a combination of EtOK/K2CO3 in Me2SO solution is described.This base-solvent system permitted the high-dilution conditions favourable to cyclization to be attained with a conveniently high rate of feed of the bifunctional reactants into the reaction medium.Yields are very good for the large rings, and still satisfactory, although significantly lower, for the medium-sized rings.
