Alonso Diego A, Nájera Carmen, Pacheco Ma Carmen
Departamento de Química Orgánica, Universidad de Alicante, Apartado 99, 03080 Alicante, Spain.
J Org Chem. 2002 Aug 9;67(16):5588-94. doi: 10.1021/jo025619t.
Oxime-derived chloro-bridged palladacycles 12 and 13 are efficient complexes for the Suzuki-Miyaura reactions of aryl-, allyl-, and benzyl halides with arylboronic acids. The isolated catalysts are thermally stable, not sensitive to air or moisture, and easily accessible from inexpensive starting materials. The reaction can be performed under aerobic conditions with aryl bromides and chlorides, displaying turnover numbers (TON) of up to 5 x 10(5) and turnover frequencies (TOF) of up to 198 000 h(-1) for aryl bromides. Aryl chlorides undergo the Suzuki reaction with arylboronic acids with TON of up to 4700 and TOF up to 4700 h(-1). Even inexpensive and readily available benzyl and allyl chlorides undergo the coupling reaction with good turnover numbers. Complexes of 12 catalyze the syntheses of symmetrical biaryls in good yields via reductive coupling of iodoarenes in the presence of Hünig's base.
肟衍生的氯桥联钯环配合物12和13是芳基卤化物、烯丙基卤化物和苄基卤化物与芳基硼酸进行铃木-宫浦反应的高效配合物。分离得到的催化剂热稳定性好，对空气或湿气不敏感，且易于从廉价的起始原料制备。该反应可在有氧条件下用芳基溴化物和氯化物进行，芳基溴化物的转化数（TON）高达5×10⁵，转化频率（TOF）高达198000 h⁻¹。芳基氯化物与芳基硼酸进行铃木反应，TON高达4700，TOF高达4700 h⁻¹。甚至廉价易得的苄基氯和烯丙基氯也能以良好的转化数进行偶联反应。配合物12能在Hünig碱存在下通过碘代芳烃的还原偶联以良好的产率催化对称联芳基的合成。
