Browne, Duncan L.; Helm, Matthew D.; Plant, Andrew; Harrity, Joseph P. A. published the artcile< A sydnone cycloaddition route to pyrazole boronic esters>, SDS of cas: 1002334-12-4, the main research area is pyrazole boronate preparation cycloaddition dipolar sydnone alkynylboronate; regioselectivity dipolar cycloaddition alkynylboronate sydnone preparation pyrazolylboronic acid.
Regioselective 1,3-cycloaddition of N-methylsydnone with alkynylboronates gave 4-pyrazolylboronic acids. Cycloaddition of pinacol alkynylboronate R1CCB(OCMe2)2 with 3-R1-5-oxy-1,2,3-oxadiazole (N-R1-sydnone) in xylene at reflux gave 1-R1-3-R2-4-B(OCMe2)-1H-pyrazoles (3a-12a; R1 = Ph, 4-MeOC6H4, 4-NO2C6H4; R2 = Ph, Bu, Me3Si, H) together with their regioisomeric 1-R1-4-R2-3-B(OCMe2)-1H-pyrazoles (3b-12b, same R1, R2) with 54-83% yields and 2:1 to 100% a/b regioselectivity. Functionalization of the products by Suzuki coupling and N-deprotection processes highlight the potential synthetic utility of these species.
Angewandte Chemie, International Edition published new progress about 1,3-Dipolar cycloaddition reaction. 1002334-12-4 belongs to class pyrazoles-derivatives, and the molecular formula is C15H19BN2O2, SDS of cas: 1002334-12-4.
Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics