Methane → Palladium

Participants

Reaction Steps

The reaction of Example 1 (reaction scale: 10 mmol of bromophenyl pyrazole) was conducted with 0.15 mole % of Pd2(dba)3. After the reaction was judged to be essentially complete, THF (10 mL/g of bromophenyl pyrazole starting material) was added to dissolve the precipitates, and the solution was passed through a Darco zeta pad twice. The filtrate was neutralized with 1N aq. HCl to a pH of 7.0 to 7.5. After filtration, the crude solid, whose palladium level was 111 ppm, was dissolved in THF (9 mL/g of bromophenyl pyrazole starting material), and the mixture was stirred in the presence of PS-PPh3 resin (Argonaut Technologies, 1.61 mmol PPh3/g, 5 wt %) at ambient temperature for 21 h, then filtered twice through a Darco zeta pad. The filtrate was concentrated and the product was recrystallized from THF/acetone/water to afford 2′-(5-ethyl-3,4-diphenyl-1H-pyrazol-1-yl)-[1,1′]-biphenyl-3-ol containing less than 2 ppm of palladium.

Provenance & Evidence