title: Reactivity of functionalized N,S-ketene acetal: regioselective construction of tetrahydrobenzo[b]pyran and chromeno[2,3-b]quinoline derivatives.
abstract: Regioselective synthesis of functionalized tetrahydrobenzo[b]pyrans has been developed by multicomponent reactions (MCRs) and tandem [3 + 3] annulations of β-benzoylthioacetanilides or β-(2-haloaroyl)thioacetanilides as valuable sources with aromatic aldehydes and 5,5-dimethyl-1,3-cyclohexanedione catalyzed by triethylamine. This MCR followed by a postcondensation cyclization via an intramolecular S(N)Ar in the presence of K(2)CO(3) led to an unprecedented novel chromeno[2,3-b]quinoline framework containing an important chromene moiety in good yields. The reactions were very mild, convenient, and o-selective to form new fused tetracyclic target molecules.
authors.affiliation: State Key Laboratory Base of Eco-Chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, 53 Zhengzhou Road, Qingdao 266042, PR China. liming928@qust.edu.cn
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.forename: Yan-Li
authors.initials: YL
authors.lastname: Hou
authors.forename: Li-Rong
authors.initials: LR
authors.lastname: Wen
authors.forename: Fu-Meng
authors.initials: FM
authors.lastname: Gong
mesh_terms: D000080:Acetals / Q000737:chemistry*; D001578:Benzopyrans / Q000138:chemical synthesis* / Q000737:chemistry*; D002384:Catalysis; D003500:Cyclization; D005030:Ethylenes / Q000737:chemistry*; D007659:Ketones / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D011804:Quinolines / Q000138:chemical synthesis* / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000080:Acetals; D001578:Benzopyrans; D005030:Ethylenes; D007659:Ketones; D011804:Quinolines; C008223:ketene