1,4-Dioxane → 4-(Benzo[b]thiophen-7-yl)isoquinoline

Participants

Reaction Conditions

Reaction Steps

A vessel capable of sealing was charged with a mixture of 7-bromobenzo[b]thiophene (430 mg, 2.018 mmol), isoquinolin-4-ylboronic acid (419 mg, 2.421 mmol), PdCl2(dppf)-CH2Cl2 adduct (82 mg, 0.101 mmol), dioxane (6 mL), and a 2.0 M aqueous solution of K3PO4 (3 mL, 1.41 mmol) and was purged with nitrogen for 10 min. The vessel was sealed and heated at 90° C. for 16 hours. Upon cooling, the reaction mixture was diluted with CH2Cl2 and filtered with CH2Cl2/MeOH washing. The filtrate was concentrated under reduced pressure. The residue was dissolved in CH2Cl2 and washed with water, brine, dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude material was purified by BIOTAGE® eluting with 0%-15% EtOAc/CH2Cl2 at 30 mL/min. Concentration of appropriate fractions provided the title compound (32 mg, 30% yield). LC/MS: Example 109A @ 2.49 min (RT) (Condition G). MS (ES): m/z=262.42 [M+H]+. 1H NMR (400 MHz, CDCl3) δ ppm 9.38 (1 hr, s), 8.71 (1 hr, s), 8.08-8.15 (1 hr, m), 7.96 (1 hr, dd, J=8.06, 1.01 Hz), 7.51-7.71 (4 hr, m), 7.39-7.51 (3 hr, m).

Provenance & Evidence