Synthesis of polyconjugated carbazolyl–oxazolones by a tandem hydrozirconation–Erlenmeyer reaction. Study of their hyperpolarizability values

New push–pull systems with carbazole as donor moiety and oxazolone as electron withdrawing group have been synthesized by an AgClO4-catalyzed hydrozirconation and ulterior Erlenmeyer reaction. Studies carried out with the semiempirical quantum method PM3 (MOPAC93) pointed a low dependence of the hyperpolarizability value on the number of double bonds at the conjugated bridge by β(0)∝n0.8. Introduction of rigidity in the polyene chain or additional donor groups in the carbazole moiety pointed to exertion of a large effect on hyperpolarizability values that could avoid unnecessary efforts in costly path elongation synthesis.