Efficient Regioselective Synthesis of Novel Condensed Sulfur–Nitrogen Heterocyclic Compounds Based on Annulation Reactions of 2-Quinolinesulfenyl Halides with Alkenes and Cycloalkenes

Abstract

The preparation of novel reagents 2-quinolinesulfenyl chloride and bromide based on available 2-mercaptoquinoline has been described. This approach opens up opportunities for the introduction of 2-quinolinesulfenyl chloride and bromide into organic synthesis. Regioselective synthesis of novel 1,2-dihydro[1,3]thiazolo[3,2-a]quinolin-10-ium derivatives in high yields has been developed by annulation reactions of 2-quinolinesulfenyl chloride and bromide with alkenes. Condensed tetracyclic products have been obtained by the reactions of 2-quinolinesulfenyl chloride and bromide with cycloalkenes. The opposite regiochemistry in the reactions with styrene, isoeugenol and 1-alkenes was discussed.

Polymerization of Primary Amines with Sulfur Monochloride to Yield Red Polymers with a Conjugated SN Backbone

“…Polythiazyl (SN) x was first synthesized in 1906 and contains alternating sulfur and nitrogen atoms along its backbone (Figure ). − It has many interesting properties such as being one of only two examples of a synthetic polymer that is metallic at room temperature under atmospheric pressure and in the absence of doping. − This polymer is also superconducting with a critical temperature of 0.3 K. − Unfortunately, its straightforward composition does not lead to simple methods to alter its structure or properties, most research has described doping with different chemicals. − This polymer has been heavily investigated since its discovery, and different methods to synthesize it and its derivatives have been developed as well as numerous potential applications that take advantage of its electrical conductivity through the alternating sulfur–nitrogen bonds. − Unfortunately, its applications are limited due to its unstable nature that leads to degradation in water or under atmospheric conditions to give a gray powder. ,,,,, Although a large diversity of small organic compounds containing sulfur–nitrogen bonds have been studied for their biological activities ,− and synthesis of transition-metal complexes, − surprisingly few polymers possess nitrogen–sulfur bonds along the backbone. ,, We recently reported the synthesis of polysulfenamides, polydiaminosulfides, and polydiaminodisulfides, but these polymers possess sp 3 hybridized carbon atoms along their backbones that interrupt conjugation. ,,,…”