2,2,6,6-Tetramethylpiperidine → 2,1,3-Benzothiadiazole, 4,7-bis(5-(trimethylstannyl)-2-thienyl)-

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Reaktionsschritte

A mechanically stirred solution of 2,2,6,6-tetramethylpiperidine (TMP) (0.55 g, 4 mmol) in dry THF (25 mL) under argon was cooled to −78° C. Next, n-butyllithium (3.9 mmol) was rapidly added to the solution. The resulting solution was allowed to warm to room temperature. It was kept at room temperature for 10 min and subsequently cooled to −78° C. again. A solution of 4,7-bis(2-thienyl)-2,1,3-benzothiadiazole in 5 mL of dry THF was then added drop-wise to the cooled solution. The resulting solution has a deep purple color and was stirred at −78° C. for 30 min. A 1M solution of trimethyltin chloride in hexanes (3.9 mL) was then added. The reaction mixture was allowed to warm to room temperature and stirred overnight. Water was added to quench the reaction. Diethyl ether was added, and the mixture was washed 3 times with 0.1M HCl to remove the TMP. The solution was then dried with MgSO4. The solvent was removed, and the final product (0.42 g, 45%) was re-crystallized in ethanol to yield orange needles. 1H NMR (CDCl3): 8.19 (d, 2H), 7.88 (s, 2H), 7.30 (d, 2H), 0.44 (s, 18H). 13C NMR (CDCl3): 152.7, 145.1, 140.2, 136.1, 128.4, 125.9, 125.8, −8.2.

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