title: Practical and Efficient Synthesis of α-Aminophosphonic Acids Containing 1,2,3,4-Tetrahydroquinoline or 1,2,3,4-Tetrahydroisoquinoline Heterocycles.
abstract: We report here a practical and efficient synthesis of α-aminophosphonic acid incorporated into 1,2,3,4-tetrahydroquinoline and 1,2,3,4-tetrahydroisoquinoline heterocycles, which could be considered to be conformationally constrained analogues of pipecolic acid. The principal contribution of this synthesis is the introduction of the phosphonate group in the N-acyliminium ion intermediates, obtained from activation of the quinoline and isoquinoline heterocycles or from the appropriate δ-lactam with benzyl chloroformate. Finally, the hydrolysis of phosphonate moiety with simultaneous cleavage of the carbamate afforded the target compounds.
authors: Centro de Investigaciones Químicas-IICBA, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, Cuernavaca 62209, Morelos, Mexico. palacios@uaem.mx.
authors: Mario
authors: M
authors: Ordóñez
authors: Departamento de Química Orgánica, Universidad de Zaragoza-CSIC, ISQCH, Zaragoza 50009, Spain. aliceiw@gmail.com.
authors: Alicia
authors: A
authors: Arizpe
authors: Departamento de Química Orgánica, Universidad de Zaragoza-CSIC, ISQCH, Zaragoza 50009, Spain. jsayago@unizar.es.
authors: Fracisco J
authors: FJ
authors: Sayago
authors: Departamento de Química Orgánica, Universidad de Zaragoza-CSIC, ISQCH, Zaragoza 50009, Spain. anisjim@unizar.es.
authors: Ana I
authors: AI
authors: Jiménez
authors: Departamento de Química Orgánica, Universidad de Zaragoza-CSIC, ISQCH, Zaragoza 50009, Spain. cativiela@unizar.es.
authors: Carlos
authors: C
authors: Cativiela
mesh_terms: D063065:Organophosphonates / Q000138:chemical synthesis* / Q000737:chemistry*; D011804:Quinolines / Q000737:chemistry*; D044005:Tetrahydroisoquinolines / Q000737:chemistry*
chemical_list: D063065:Organophosphonates; D011804:Quinolines; D044005:Tetrahydroisoquinolines; C542964:1,2,3,4-tetrahydroquinoline
keywords: N-acyliminium ions; conformationally constrained; α-aminophosphonic acids