144489-88-3Relevant academic research and scientific papers
Samarium-promoted diastereoselective reductive coupling of optically active imines
Yanada, Reiko,Negoro, Nobuyuki,Okaniwa, Masanori,Miwa, Yoshihisa,Taga, Tooru,Yanada, Kazuo,Fujita, Tetsuro
, p. 537 - 540 (2007/10/03)
The intermolecular pinacol-like coupling of optically active imines was performed stereoselectively with metallic samarium and a catalytic amount of iodine to give chiral C2-2,2'-ethylenediimino-diethanol derivatives.
Synthesis of Nitrogen-Containing Macrocycles with Reductive Intramolecular Coupling of Aromatic Diimines
Kise, Naoki,Oike, Hideaki,Okazaki, Eiichi,Yoshimoto, Masami,Shono, Tatsuya
, p. 3980 - 3992 (2007/10/02)
Reductive intramolecular coupling of aromatic diimines is an effective method for the synthesis of a variety of nitrogen-containing macrocycles. 1,4-Diazacrown ethers 3 were effectively synthesized by intramolecular coupling of bis(imino ethers) 9 promoted by electroreduction (method A) or chemical reduction with zinc powder (method B) in the presence of methanesulfonic acid.In spite of the formation of macrocycles, the yields of 3 were relatively high.This can be explained by the formation of proton-bridged intermediates 14, in which intramolecular hydrogen bonds are formed between hydrogen and oxygen atoms of diiminium salts.Method B was more effective in the formation of 1,4-diaza-12-crown-4 derivatives 3 (n = 1) due to the template effect of Zn(2+).Optically active macrocyclic bislactones 4 were synthesized stereoselectively by reductive intramolecular coupling of bis(imino esters) 20 with zinc powder (method B).The high stereoselectivity is explained by considering proton-bridged intermediate 23.The resultant compounds 4 were transformed to optically active 1,2-diarylethylenediamines 7.Various sizes of macrocyclic bislactams 5 were synthesized by reductive intramolecular coupling of bis(imino amides) 26 with zinc powder (method B).Reduction of 5 gave the corresponding macrocyclic polyamines 6.
A novel method for stereoselective synthesis of (1R,2R)-diarylethylenediamines by reductive intramolecular coupling of aromatic diimines
Shono, Tatsuya,Kise, Naoki,Oike, Hideaki,Yoshimoto, Masami,Okazaki, Eiichi
, p. 5559 - 5562 (2007/10/02)
Reduction with zinc has been found to be an effective method for selective synthesis of (1R,2R)-diarylethylenediamines from the corresponding chiral aromatic diimines through their intramolecular coupling.
