160-14-5Relevant academic research and scientific papers
Lewis acid catalyzed reactions of thioketones with 1,2-epoxycyclohexane and 1,2-epoxycyclopentane
Blagoev, Milen,Linden, Anthony,Heimgartner, Heinz
, p. 2316 - 2335 (1999)
Non-enolizable thioketones and 1,2-epoxycyeloalkanes undergo a Lewis acid catalyzed addition reaction to give 1,3-oxathiolanes. Appropriate reaction conditions are CH2Cl2 as the solvent BF3. Et2O as the Lewis acid, and a temperature between -78°and r.t. Under the reaction conditions, the 1,3-oxathiolanes are only moderately stable. They decompose to yield the corresponding epithiocycloalkane and ketone. In general, 1,3-dithiolanes are isolated as minor products or, after prolonged reaction, as the main product. These secondary products are formed via the Lewis acid catalyzed reaction of the intermediate epithiocycloalkane and a second molecule of the thioketone. In the reaction of thiobenzophenone and 1,2-epoxycyclohexane, trans-8,8- diphenyl-7,9-dioxabicyclo[4.3.0]nonane is formed in small amounts as an additional side product (Scheme 12). In all cases, the newly formed heterocycle and the carbocycle are trans-fused. This result is consistent with a nucleophilic ring-opening of the complexed oxirane by the thioketone via inversion of the configuration and subsequent formation of the O(1)-C(2) bond of the 1,3-oxathiolane (Scheme 13). The surprising formation of the fused 1,4-oxathiepan derivative 23 (Scheme 9) is in accordance with an ionic reaction mechanism (cf. Scheme 15).
STUDIES ON ORGANOPHOSPHORUS COMPOUNDS-XL. REACTIONS OF KETONES WITH 2,4-BIS(4-METHOXYPHENYL)-1,3,2,4-DITHIADIPHOSPHETANE 2,4-DISULFIDE
Scheibye, S.,Shabana, R.,Lawesson, S.-O.,Romming, C.
, p. 993 - 1002 (2007/10/02)
Cyclohexanone and cyclopentanone react with (2,4-bis-4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide (Lawesson Reagent (LR)) at 80 deg C with formation of new spiro-1,3,5,2-trithiaphosphorines 1 and 2, respectively. 2-Methyl and 2-phenylcyclohexanone also react with LR at 80 deg C producing the enethiols 3 and 4, which on storage are transformed into the sulfides 5 and 6.Unsaturated cyclohexanones 7-9 are transformed into the corresponding thioketones 10-12 after reactions with LR at 60 deg C for a few hours. 2-Hydroxyketones react with LR with formation of 1,3,2-oxathiaphospholes and similarly a 2-aminoketone gave a 1,3,2-thiazaphosphole.Aromatic ketones, reacted with LR to give corresponding thioketones.Thiofluorenone dimerized to form the cyclic disulfide 31, as proved by X-ray analyses.
