Regio- and stereoselective intramolecular hydroalkoxylation of aromatic alkynols: an access to dihydroisobenzofurans under transition-metal-free conditions
An efficient, transition-metal-free method to synthesize dihydroisobenzofuran derivatives via intramolecular hydroalkoxylation of aromatic alkynols with the promotion of cesium carbonate has been developed. The reaction proceeds regioselectively with exclusive formation of 5-exo-dig product, and only Z-isomer of the new generated double bond is observed. This new protocol features with milder reaction conditions, more convenient operation and satisfactory selectivities.
Construction of Six-Membered Silacyclic Skeletons via Platinum-Catalyzed Tandem Hydrosilylation/Cyclization with Dihydrosilanes
Catalytic silicon-carbon or silicon-heteroatom bond-forming hydrosilylation has become increasingly important in synthetic chemistry, catalysis and organosilicon chemistry. Herein we report a platinum-catalyzed one-pot and tandem hydrosilylation/cyclization of OH-containing alkynes with dihydrosilanes, allowing for facile synthesis of six-membered organosilicon compounds, including silyloxycycles and cyclic siloxanes in high yields and with good stereoselectivities. (Figure presented.).