Tributylvinyltin → 1-[(2-Methoxy-5-methylphenyl)sulfonyl]-4-vinylindoline

Participants

Reaction Conditions

Reaction Steps

4-bromo-1-[(2-methoxy-5-methylphenyl)sulfonyl]indoline (tot 721 mg, 1.89 mmol; Intermediate 9), tributyl(vinyl)stannane (tot 1.10 mL, 3.78 mmol) and Pd(PPh3)2OAc2 (tot 142 mg, 0.19 mmol) in dry toluene (tot 12 mL) was distributed into 3 tubes and stirred at 110° C. using a STEM block over weekend (68 h). Still about 30% starting material. The reactions were combined, filtered and concentrated. Redissolved in dry MeCN (8 mL), distributed into 2 Micro wave tubes followed by addition of tributyl(vinyl)stannane (300 μL, 1.03 mmol) and Pd(PPh3)2OAc2 (30 mg, 0.04 mmol) to each tube. The mixtures were irradiated by micro waves 180° C. for 600 s. Filtration and concentration followed by purification by flash (30% hexane in DCM) gave the title compound (300 mg, 48%) as a colorless viscous oil. MS (ESI+) for C18H19NO3S m/z 330 (M+H)+.

Provenance & Evidence