Collect. Czech. Chem. Commun. 1987, 52, 2281-2294

Reaction of 6,11-dihydrodibenzo[b,e]thiepin-11-carbonitrile with 1,2-dibromoethane, a reinvestigation. Formation of 11,12-dihydro-6H-6,12-methanodibenzo[b,f]thiocin-12-carbonitrile

Karel Šindelářa, Miloš Buděšínskýb, Tomáš Vaněkb, Jiří Holubeka, Emil Sváteka, Oluše Matoušováa, Charles Wayne Reesc and Miroslav Protivaa

a Research Institute for Pharmacy and Biochemistry, 130 60 Prague 3, Czechoslovakia
b Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, 166 10 Prague 6, Czechoslovakia
c Department of Chemistry, Imperial College of Science and Technology, London SW7 2AY, U.K.


Reinvestigation of the minor product of reaction of 6,11-dihydrodibenzo[b,e]thiepin-11-carbonitrile (I) with 1,2-dibromoethane in the presence of tetrabutylammonium bromide or benzyltriethylammonium chloride and 50% sodium hydroxide by means of 1H and 13C NMR spectroscopy led to the formula XI named in the title, which was confirmed by X-ray crystallographic analysis. The product of a similar reaction, carried out in dimethyl sulfoxide in the presence of potassium carbonate at 100 °C was identified as the stereoisomeric mixture of 11,11'-ethylenebis(6,11-dihydrodibenzo[b,e]thiepin-11-carbonitriles) (XII) which was separated to the components by preparative HPLC. The title compound XI was oxidized to the sulfoxide XIII and the sulfone XIV, and was transformed by reduction and the following methylation to amines XV and XVI. The reduction of the vinyl nitrile III with lithium aluminium hydride is complicated on the one hand by allylic rearrangement, and with cyanide anion abstraction on the other, the products being (E,Z)-mixture of 3-(6,11-dihydrodibenzo[b,e]thiepin-11-ylidene)propylamines (XVII) and 11-vinyl-6,11-dihydrodibenzo[b,e]thiepin (X). The amine XVI is devoid of thymoleptic activity.