Heterocycle formation via palladium-catalyzed intramolecular oxidative C− H bond functionalization: an efficient strategy for the synthesis of 2-aminobenzothiazoles
LL Joyce, RA Batey
文献索引:Joyce, Laurie L.; Batey, Robert A. Organic Letters, 2009 , vol. 11, # 13 p. 2792 - 2795
N-Arylthioureas are converted to 2-aminobenzothiazoles via intramolecular C− S bond formation/C− H functionalization utilizing an unusual cocatalytic Pd (PPh3) 4/MnO2 system under an oxygen atmosphere at 80° C. This method eliminates the need for an ortho-halo substituted precursor, instead achieving direct functionalization of the ortho-aryl C− H bond. Mechanistic observations, including a large intramolecular primary kinetic isotope effect of ...