Synthesis 2010(18): 3091-3096  
DOI: 10.1055/s-0030-1258171
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

A Facile and Practical Solvent-Free One-Pot Synthesis of (Z)-4-Methylene-3-selenaquinoline Derivatives from o-Ethynylanilines and Isoselenocyanates [¹]

Haruki Sashida*a, Chao Pana, Mamoru Kanamea, Mao Minourab
a Faculty of Pharmaceutical Sciences, Hokuriku University, Kanagawa-machi, Kanazawa 920-1181, Japan
e-Mail: h-sashida@hokuriku-u.ac.jp;
b Department of Chemistry, School of Science, Kitasato University, 1-15-1 Kitasato, minami-ku, Sagamihara, Kanagawa 252-0373, Japan
Further Information

Publication History

Received 20 April 2010
Publication Date:
12 July 2010 (online)

Abstract

Heating of o-ethynylanilines with isoselenocyanates directly resulted in the 6-exo-dig mode ring-closure reaction of the adducts to give the (Z)-2-imino-4-methylene-3-selenaquinolines in moderate to good yields. Based on this convenient, solvent-free, catalyst-free method, several 3-selenaquinoline derivatives (3,1-benzoselenazines) were easily obtained in one pot. Successful application of the microwave-assisted synthesis of these compounds was also investigated.

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Single crystals of 3Dd were obtained from solns of CHCl3 after slow evaporation of the solvent at r.t. Diffraction data were collected on a Bruker Apex-II CCD. The structure analysis is based on 2629 observed reflections with I > 2.00σ(I) and 217 variable parameters; colorless prisms, C21H16N2Se, FW = 375.32, 233 K, monoclinic, space group P21/n, a = 10.3882(7) Å, b = 8.3928(5) Å, c = 19.432(1) Å, β = 91.164(1)˚, V = 1693.9(2) ų, Z = 4, R = 0.0288, R w  = 0.0759, GOF = 1.037. The supplementary crystallographic data for 3Dd (CCDC-773220) can be obtained free of charge from the Cambridge Crystallographic Data Centre via http://www.ccdc.cam.ac.uk/products/csd/request/request.php4.