Triphenylphosphine → 1-(6,7-Di-vinyl-2-benzothiazolyl)-3-ethylurea

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Similar to the synthesis of Example 203, a mixture of 1-(6-bromo-7-trifluoromethylsulfonyl-2-benzothiazolyl)-3-ethylurea (0.100 g, 0.22 mmol), lithium chloride (0.078 g, 1.84 mmol, 8.4 eq), triphenylphosphine (0.034 g, 0.13 mmol, 0.6 eq), Pd(PPh3)2Cl2 (0.018 g, 0.026 mmol, 0.12 eq), tetravinyltin (0.080 mL, 0.44 mmol, 2.0 eq), and a crystal of 2,6-di-tert-butyl-4-methylphenol was purged with nitrogen gas, and was heated at about 100° C. for about 18 hours. Additional tin reagent (0.080 mL, 0.44 mmol, 2.0 eq) was added to the mixture after the first 2 hours. The mixture was taken up in MeOH, filtered, and concentrated. Purification by HPLC and flash chromatography on SiO2 with ethyl acetate/methylene chloride (1/4) gave the desired compound 0.014 g (23%). LC/MS 274.3 (M+1); LC retention time 2.32 min.

Herkunft & Nachweise