1622332-58-4Relevant academic research and scientific papers
Ring-expanded chiral rhombamine macrocycles for efficient NMR enantiodiscrimination of carboxylic acid derivatives
Tanaka, Koichi,Iwashita, Tomoharu,Sasaki, Chihiro,Takahashi, Hiroki
, p. 602 - 609 (2014)
Novel 46-membered chiral rhombamine macrocycles (R,R,R,R)-8a and 8b were synthesized by [2+2] cyclocondensation reactions of (R,R)-1,2-diaminocyclohexane with the corresponding dialdehydes and subsequent reduction with NaBH 4. The X-ray crystal structure of 1:4 dioxane complex with (R,R,R,R)-8a indicated a rhombus conformation of the chiral macrocycle. Compounds (R,R,R,R)-8a and 8b were tested as chiral shift reagents for a wide range of α-substituted carboxylic acids and amino acid derivatives. Enantiodiscrimination of 1H NMR signals was observed with ΔΔδ values of up to 0.214 ppm.
