17792-13-1Relevant articles and documents
Reactions of ethyl diazoacetate with thioketones
Kaegi,Mloston,Heimgartner
, p. 678 - 687 (2007/10/03)
The reaction of ethyl diazoacetate (10) with 9H-fluorene-9-thione (2a), thiobenzophenone (2b), and adamantanethione (2c), respectively, in THF yielded 1,3-dithiolane carboxylates (Scheme 2). Whereas in the first two cases the reaction proceeded at room temperature, heating to 60°C was necessary when the less reactive 2c was used. The additions with 2a and 2c occurred in a regioselective way, yielding 1,3-dithiolane-2-carboxylate 11a and 1,3-dithiolane-4-carboxylate 12c, respectively, with opposite regiochemistry. On the other hand, a mixture of the two regioisomeric cycloadducts 11b and 12b was formed in the case of 2b. The analogous reaction of 10 with the sterically crowded thione 13 gave thiirane 14 as the sole product, and with the corresponding dithione 16, a mixture of the cis-and trans-dithiiranes 17 and 18 was formed (Scheme 3). Desulfurization with tris(dimethylamino)phosphine yielded the α,β-unsaturated esters 15 and 19/20, respectively. The α,β-unsaturated ester 22 was the only product in the reaction of 10 with 9H-xanthene-9-thione (21), which had to he carried out at 60°C.
