97129-85-6Relevant academic research and scientific papers
ACID-BASE REACTIONS OF 1,3,4-THIADIAZOLINES AND THIOCARBONYL YLIDES; 1,3,4-THIADIAZOLINE-2-SPIRO-2'-ADAMANTANE
Mloston, Grzegorz,Huisgen, Rolf
, p. 1053 - 1056 (1985)
The surprising formation of C22H32N2S2 from the title compound 1 at 45 oC involves the interaction of the basic adamantanethione S-methylide (2) with its acidic precursor 1, in the course of which the anion 6 undergoes electrocyclic ring opening; the acid and base functions offer the clue to a prolific chemistry of the thiadiazoline 1 and the thiocarbonyl ylide 2.
Adamantanethione and diazomethane; dual regiochemistry of cycloadditions [1]
Huisgen,Mloston
, p. 635 - 644 (2007/10/03)
Cydoaddilions of diazoalkanes to thiones take place in two directions furnishing 1,3,4-thiadiazolines and/or their 1,2,3-isomers, depending upon the substituents. Adamantanethione and diazomethane give rise to hoth regioisomers; a literature report on the high solvent dependence of the isomer ratio is confirmed, and the two regioisomers are isolated. The 1,3,4-thiadiazoline 20 eliminates N2 at 80°C (t1/2 55 s) in a 1,3-dipolar cycdoreversion: the thiocarbonyl ylide 22 generated undergoes electrocyclization, forming a thiirane, or is intercepted by reactions with HX (thiols, alcohols) or dipolarophilic multiple bonds. The N2 extrusion from the isomeric 1,2,3-thiadiazoline 21 is at 80°C 600 times slower: the formation of the spirothiirane and homoadamantane-2-thione is explained by a diazonium thiolate as an intermediate.
