Friedel–Crafts chemistry 56. Unprecedented construction of functionalized polycyclic quinolines via Friedel–Crafts cycliacylation and Beckmann rearrangement

• Published in: Chemistry of heterocyclic compounds (New York, N.Y. 1965) Vol. 55; no. 7; pp. 632 - 643
• Main Authors: Abd El-Aal, Hassan A. K., Khalaf, Ali A.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.07.2019; Springer Nature; Springer; Springer Nature B.V
• Subjects: Acylation; Chemical industry; Chemistry; Chemistry and Materials Science; Chemistry, Organic; Esters; Friedel-Crafts reaction; Ketones; Organic Chemistry; Organic compounds; Oximes; Pharmacy; Physical Sciences; Pyrazole; Science & Technology; azocinoquinolinone; azepinoquinolinone; azoninoquinolinone; Beckmann rearrangement; Friedel–Crafts reaction; cycliacylation; cycloheptaquinolinone; ASYMMETRIC-SYNTHESIS; ALKYLATION; AROMATIC-COMPOUNDS; CYCLIALKYLATIONS; FACILE SYNTHESIS; REGIOSELECTIVE SYNTHESIS; EFFICIENT; DERIVATIVES; Friedel-Crafts reaction; CYCLIZATION; SUBSTITUTED QUINOLINES
• ISSN: 0009-3122; 1573-8353
• DOI: 10.1007/s10593-019-02509-2

Construction of functionalized tetracyclic pyrazolo-fused cyclohepta[2,3- h ]-, azepino[4,5- h ]-, azocino[5,4- h ]-, azocino[4,5- h ]-, azonino[5,6- h ]-, and azocino[2,3- h ]quinolinones has been demonstrated by performing intramolecular Friedel–Crafts acylation and Beckmann rearrangement. Trifluoromethanesulfonic or polyphosphoric acid-assisted cyclization of N-heterocyclic acids and esters, synthesized from 1-phenyl-3-(quinolin-8-yl)-1 H -pyrazole-4-carbaldehyde, allows to obtain tetracyclic ketones. Further polyphosphoric acid-mediated Beckmann rearrangement of cyclohepta[1,2- h ]quinolinone oximes provides the respective lactams in high yields.