90877-62-6

Upstream product

• 80041-89-0 isopropylboronic acid 
• 75344-77-3 4-bromo-3,5-dimethyl benzonitrile 
• 955929-58-5 4-cyano-2,6-dimethylphenyl trifluoromethanesulfonate 
• 4198-90-7 3,5-dimethyl-4-hydroxybenzonitrile 

Relevant academic research and scientific papers

Efficient cross-coupling of aryl/alkenyl triflates with acyclic secondary alkylboronic acids

Aryl-secondary alkyl cross-coupling with aryl sulfonate esters as coupling partners remains a significant challenge. Efficient cross-coupling between aryl/alkenyl triflates and acyclic secondary alkylboronic acids is realized for the first time to provide a series of sterically congested acyclic secondary alkyl arenes/olefins in good to excellent yields. The employment of sterically bulky P,PO ligand L1/L2 is crucial for the high yields and selectivities. The method has enabled a concise and 4-step synthesis of a key intermediate of male contraceptive agent and PAF antagonist gossypol.

Efficient synthesis of sterically hindered arenes bearing acyclic secondary alkyl groups by suzuki-miyaura cross-couplings

Bulky P,P-O ligands were designed to inhibit isomerization and reduction side reactions during the cross coupling between sterically hindered aryl halides and alkylboronic acids. Suzuki-Miyaura cross-couplings between di-ortho-substituted aryl bromides and acyclic secondary alkylboronic acids have been achieved with high yields. The method has also enabled the preparation of ortho-alkoxy di-ortho-substituted arenes bearing isopropyl groups in excellent yields. The utility of the synthetic method has been demonstrated in a late-stage modification of estrone and in the application to a new synthetic route toward gossypol. No side reaction: The shown bulky P,P-O ligands (right) successfully inhibit isomerization and reduction side reactions of the cross-coupling of sterically hindered substrates such as di-ortho-substituted aryl bromides with acyclic secondary alkylboronic acids. The method also allows the preparation of ortho-alkoxy di-ortho-substituted isopropyl arenes in excellent yields.