75544-10-4

Upstream product

• 1116155-54-4 2-(diisopropylphenylsilyl)phenyl trifluoromethanesulfonate 
• 1888-75-1 isopropyllithium 
• 80-10-4 diphenylsilyl dichloride 

Relevant academic research and scientific papers

SILICIUM-VERBINDUNGEN MIT STARKEN INTRAMOLEKULAREN STERISCHEN WECHSELWIRKUNGEN X. NEUE WEGE ZU 1,3,2,4-DITHIADISILETANEN

2,2,4,4-Tetraorganyl-1,3,2,4-dithiadisiletanes containing bulky organyl groups are obtained by copyrolysis of the disilanes R3Si-SiR3 with sulfur or sulfur hexafluoride, or better by reaction of the disilanes R2HSi-SiHR2 (R=CH3, i-C3H7, cyclo-C6H11, t-C4H9) with sulfur.In the case of R=t-C4H9 a considerable amount of the t-butyl groups is isomerized to the less crowded isobutyl groups.Monomeric silathiones R2Si=S are not available by this route.The sulfur insertion reaction into 1,1-di-t-butyl-1-silacyclobutane yields 2,4-di-t-butyl-2,4-dipropyl-1,3,2,4-dithiadisiletane instead of the expected 1,1-di-t-butyl-1-sila-2-thiacyclopentane.The latter compound, however, results from the crown ether catalyzed cyclisation reaction of 3-bromopropyltrichlorosilane with Na2S followed by transalkylation with t-butyllithium.The iodosilanes R3SiI (R=i-C3H7, cyclo-C6H11) react with Na2S to give the corresponding hexaorganyldisilathianes in high yields.

Palladium-Catalyzed Intramolecular C?H Arylation versus 1,5-Palladium Migration: A Theoretical Investigation

Theoretical investigations were carried out to elucidate the origin of chemoselectivity in the palladium-catalyzed reactions of 2-(dimethylphenylsilyl)phenyl triflates with or without an amino group at the 3-position. The selective formation of a 5,10-dihydrophenazasiline rather than a dibenzosilole from the substrate with an amino group at the 3-position could be successfully explained by proposing a new 1,5-palladium migration pathway that involves a neutral diorganopalladium(II) intermediate along with the subsequent formation of a low-energy amine-coordinated palladacycle intermediate prior to the C?N bond-forming process.