479191-68-9Relevant academic research and scientific papers
Facile N-Derivatization of α-Amino Esters and Amides via Benzotriazolylmethyl Derivatives
Katritzky, Alan R.,Kirichenko, Nataliya,Rogovoy, Boris V.,He, Hai-Ying
, p. 9088 - 9092 (2007/10/03)
α-(N-Substituted amino)esters were prepared in a two-step procedure from available unsubstituted α-amino esters. α-Amino esters are first converted into the corresponding N-benzotriazolylmethyl derivatives; in the second step, the benzotriazole group is substituted by various nucleophiles with or without the presence of a Lewis acid to give substituted α-amino esters in high overall yield under mild conditions with no signs of racemization. Boc-protected amino acids were converted into α-amino amides; subsequent deprotection allowed the conversion into N-substituted derivatives analogously to the α-amino esters, without racemization in high yields under mild conditions.
Novel syntheses of enantiopure hexahydroimidazo[1,5-b]isoquinolines and tetrahydroimidazo[1,5-b]isoquinolin-1(5H)-ones via iminium cation cyclizations
Katritzky, Alan R.,Suzuki, Kazuyuki,He, Hai-Ying
, p. 8224 - 8229 (2007/10/03)
Condensations of chiral diamines 11a-c with benzotriazole and formaldehyde gave benzotriazolyl intermediates 12a-c; similar condensations of α-amino-amides 10a-c with benzotriazole and paraformaldehyde gave 14a-c. Subsequent treatment of 12a-c and 14a-c with AlCl3 led to enantiopure tricyclic 1,2,3,5,10,10a-hexahydroimidazo[1,5-b]isoquinolines 1a-c and 2,3,10,10a-tetrahydroimidazo[1,5-b]isoquinolin-1(5H)-ones 15a-c, respectively, via Lewis acid promoted iminium cation cyclizations.
