385837-76-3

Upstream product

• 220972-34-9 1,2:5,6-di-O-isopropylidene-α-D-glucofuranosyl (S)-cyclohexanesulfinate 
• 226709-30-4 (R)-2-(Cyclohexylsulfinyl)-N,N-dimethylethanethioamide 
• 41719-04-4 Cyclohexanesulfinyl chloride 
• 385837-68-3 (SS)-1-[(Z)-but-2-enylsulfanyl]-2-(cyclohexylsulfinyl)-1-(N,N-dimethylamino)-(Z)-ethene 

Relevant academic research and scientific papers

Asymmetric thio-claisen rearrangement induced by an enantiopure alkylsulfinyl group. Unusual preference for a boat transition state in the acyclic series

Ketene aminothioacetals 2a-c and 5a-b bearing an enantiopure vinylic alkylsulfinyl substituent were readily prepared from (R)-2-cyclohexylsulfinyl-N,N-dimethylethanethioamide 1 with full control of the geometry of their double bonds. They underwent a Claisen rearrangement upon heating at THF reflux to afford α-sulfinyl ?-unsaturated thioamides 3a-c and 6a-b. With all substrates the asymmetric induction of the sulfinyl group was excellent. The determination of the absolute configurations of thioamides 3a-c and 6a-b was achieved either by X-ray crystallographic analysis or by chemical correlation. The stereochemical course of this [3,3] sigmatropic transposition was explained by an electronic model. Interestingly the Claisen rearrangement of the (ZE)-cinnamyl substrates 5b was shown to proceed through a boat transition state rather than a chair transition state; such a preference is quite unusual for acyclic systems.