Triphenylphosphine → 1-(4-Chloro-phenyl)-3-((Z)-3-tributylstannanyl-but-2-enyloxy)-1H-pyrazole

Participants

Reaction Conditions

Reaction Steps

To 8.09 g (30.8 mmol) triphenylphosphine in 200 ml THF have been added with stirring at −75° C. 6.23 g (30.8 mmol) azodicarbonic acid diisopropyl ester. The mixture has been stirred at this temperature for 5 min. Then 10.39 g (28.8 mmol) (Z)-3-tributylstannanyl-but-2-en-1-ol have been added dropwise and stirred for 5 min at −75° C. After addition of 4.00 g (20.6 mmol) 1-(4-chlorophenyl)-3-hydroxypyrazole at −75° C. a red suspension was formed. The mixture was allowed to warm up to ambient temperature and stirred for 3 d. After removal of the solvents in vacuo 29 g oil have been collected and purified by chromatography on 120 g silica with MTBE/heptane. Yield 8.3 g (75%) oil. δ=0.85 (m); 0.95 (m); 1.30 (m); 1.50 m); 2.00 (s); 4.65 (d); 5.90 (d); 6.43 (t); 7.35 (d); 7.52 (d); 7.68 (d).

Provenance & Evidence