176243-97-3

Upstream product

• 38762-70-8 bis(4-methoxyphenyl)diselenide 
• 64161-50-8 (1S,4R)-1-(bromomethyl)-7,7-dimethylbicyclo-[2.2.1]heptan-2-one 
• 176244-03-4 (1S,3R,5R,7R)-3-Chloro-3-(4-methoxy-phenyl)-10,10-dimethyl-4-oxa-3λ⁴-selena-tricyclo[5.2.1.0^1,5]decane 
• 176243-99-5 (1S,4R)-1-(4-Methoxy-phenylselanylmethyl)-7,7-dimethyl-bicyclo[2.2.1]heptan-2-one 
• 176244-01-2 (1S,2R,4R)-1-(4-Methoxy-phenylselanylmethyl)-7,7-dimethyl-bicyclo[2.2.1]heptan-2-ol 
• 80095-52-9 Lithium; 4-methoxy-benzeneselenolate 

Relevant academic research and scientific papers

First synthesis of optically pure selenuranes and stereoselective alkaline hydrolysis. Their application to asymmetric [2,3] sigmatropic rearrangement of allylic selenoxides

The first synthesis of optically pure selenuranes 1 has been accomplished by utilizing 2-exo-hydroxy-10 bornyl group as a chiral ligand Complete retention of the configuration has been observed in alkaline hydrolysis of 1 to give selenoxides 2. The structure of 1 and 2 has been fully established by X-ray crystallography. [2,3] Sigmatropic rearrangement of allylic selenoxides 2 gave the corresponding allylic alcohols 3 with up to 88% enantiomeric excess (ee). The [2,3] sigmatropic rearrangement of allylic selenoxides 2 progresses predominantly via an endo transition state.

Enantioface-differentiating protonation with chiral γ-hydroxyselenoxides

Enantioface-differentiating protonation of a chiral metal enolates of α-alkylcarbonyl compounds 7 has been developed using chiral γ-hydroxyselenoxides 1 as a proton source. Reaction of zinc bromide enolates of 2-benzyl- and 2-n-propylcyclohexanones with (S(Se))-1e gave (S)-2-benzylcyclohexanone 7a and (R)-2-n-propylcyclohexanone 7c in high enantiomeric excess, respectively. Intramolecular hydrogen bonding of the selenoxide 1, chelation effects between 1 and metal enolate, and 2-exo-hydroxy-10-bornyl-framework could contribute to this asymmetric induction.

The first example of enantioselective protonation of prochiral enolates with chiral γ-hydroxyselenoxides

Enantioselective protonation of a simple enolate has been developed using an optically pure γ-hydroxyselenoxide 1 as a chiral proton source. Reaction of zinc bromide enolate 7b with (Sse)-selenoxide (Sse)-1c gave (S)-2-benzylcyclohexanone (S)-8 with high enantioselectivity. Intramolecular hydrogen bonding between hydroxy group and seleninyl-oxygen of 1 would contribute to this asymmetric induction.