Synthése et réactivité de di(2-F-alkyléthylthio)méthanes et de leurs produits d'oxydation. I. Alkylation

Transformation of Zwitterionic Pyridine Derivatives to a Spiro-Fused Ring System: Azoniabenzo[de]fluorine. Synthesis and Mechanistic Rationalization

Reaction of aryl- and benzylsulfanopyridinium amidates bearing a methyl group in position 6 with 2 equiv of diphenylketene afforded a spiro-fused ring system: azoniabenzo[de]fluorine. By use of an excess amount of ketene, a distinct reaction was observed via which a 1H-pyrrolo[3,2-b]pyridin-2(3H)-one derivative was furnished. The structure of the tetracyclic spiro-fused ring system was unambiguously confirmed by X-ray diffraction, and its formation was rationalized by DFT calculations.

Synthesis of novel ([oligomethylene]alkane-α,ω-diyl) bis(diallylcarbamodithioates); monomers as precursors for RAFT photoplastic polymer networks

An efficient three-component coupling reaction of N,N-diallylamine, carbon disulfide, and bis(allyl chlorides) of the type β,ω-bis(chloromethyl)poly(glycolyl)-α,ω-dienes and other such compounds, in the presence of excess triethylamine in chloroform, has been established. The resulting mixtures gave after aqueous workup novel ([oligomethylene]alkane-α,ω-diyl) bis(diallylcarbamodithioates) that may also function as useful monomers for RAFT-based photoplastic polymer networks.

New facile tandem route to oxo- and thioxo[1,2,4]triazolo[1,5-a]pyridinium salts

2-Arylsulfanyl- and benzylsulfanylpyridinium N-arylimides (2), easily available from tetrazolo[1,5-b]pyridinium salts (1), participate in 1,3-dipolar cycloaddition with aryl isothiocyanates and aryl isocyanates to result in formation of fused thioxo- and oxo[1,2,4]triazolium salts (5 and 12), respectively. This transformation is interpreted as a regular 1,3-cycloaddition followed by spontaneous elimination of the aryl- or benzylsulfanyl group. Formation of these triazolium salts can be followed--under appropriate reaction conditions--by ring-opening reactions to afford some new triazolyldienes (6). Recognition of the intermediate participation of the thiolate anion along the pathway 1 --> 5 allowed elaboration of a simple procedure to 5 implying a tandem reaction sequence.

Rhodium-Catalyzed Reaction of Thiols with Polychloroalkanes in the Presence of Triethylamine

[reaction: see text] RhCl(PPh(3))(3) catalyzes a reaction of thiols with polychloroalkanes in the presence of triethylamine. This reaction serves as a convenient new method to produce formaldehyde dithioacetals, ethylenedithioethers, thioformates, and dithiocarbonic esters under mild conditions.