title: Cyano-Schmittel Cyclization through Base-Induced Propargyl-Allenyl Isomerization: Highly Modular Synthesis of Pyridine-Fused Aromatic Derivatives.
abstract: The cyano-Schmittel cyclization of in situ-generated cyano-allenes has been carried out. The DFT calculation results suggest that the diradical pathway plays a major role in this cyclization. The reactions can be conveniently performed in a one-pot manner through cascade Sonogashira coupling of terminal cyano-ynes with organic halides, followed by base-promoted propargyl-allenyl isomerization/cyclization, leading to an efficient access to pyridine-fused polycyclic architectures. In particular, a large variety of aryl or heteroaryl rings such as furans, thiophenes and pyridines can be incorporated into the follow-up cyano-Diels-Alder reactions, highlighting the great synthetic utility of this chemistry.
authors.affiliation: State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032 (P. R. China), Fax: (+86)021-64166128.
authors.forename: Xu
authors.initials: X
authors.lastname: You
authors.affiliation: State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032 (P. R. China), Fax: (+86)021-64166128.
authors.forename: Xin
authors.initials: X
authors.lastname: Xie
authors.affiliation: State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032 (P. R. China), Fax: (+86)021-64166128.
authors.forename: Haoyi
authors.initials: H
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032 (P. R. China), Fax: (+86)021-64166128.
authors.forename: Yuxue
authors.initials: Y
authors.lastname: Li
authors.affiliation: State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032 (P. R. China), Fax: (+86)021-64166128. yhliu@mail.sioc.ac.cn.
authors.forename: Yuanhong
authors.initials: Y
authors.lastname: Liu
keywords: alkynes; cyano-Schmittel cyclization; indenoquinoline; nitriles; propargyl-allenyl isomerization