Gayen Sourav, Shyamal Sampad, Mohapatra Stutee, Antharjanam P K Sudhadevi, Ghosh Sundargopal
Department of Chemistry, Indian Institution of Technology, Madras, Chennai, 600036, India.
SAIF, Indian Institute of Technology, Madras, Chennai, 600036, India.
Chemistry. 2024 Jan 26;30(6):e202302362. doi: 10.1002/chem.202302362. Epub 2023 Dec 12.
In an effort to establish B-P coupling reactions without the use of phosphine-borane dehydrocoupling agent, we have developed a new synthetic methodology employing group 8 metal σ-borate complex [{κ -H,S,S'-BH L }Ru{κ -H,H,S-BH L}] (L=NC H S), 1. Treatment of 1 with chlorodiphenyl phosphine (PPh Cl) yielded 1,5-P,S chelated Ru-dihydridoborate species [PPh H{κ -H,H,S-BH(OH)L}Ru{κ -P,S-(Ph P)BH L}], 2. The insertion of phosphine moiety (PPh ) by the cleavage of 3c-2e σ(Ru H-B) bonding interaction led to the formation of B-P bond. The κ -P,S chelated six-membered ring adopted a boat conformation in complex 2. The heterocycle is made of all different atoms, which is one of the rarest examples of heteroatomic ring systems. Theoretical outcomes demonstrated the electronic insight of B-P coupling and stabilization through transition metal. In order to explore an alternate route of B-P bond formation, we have further explored the reaction of 1 and Ru-bis(dihydridoborate) complex, 5 with secondary phosphine oxide (SPO). Although, thermolysis of 1 with diphenylphosphine oxide yielded analogous σ-borate complex 3, the similar reaction of 5 at room temperature led to the formation of novel phosphinous(III) acid incorporated Ru(σ-borate)(dihydridoborate) complex, 6. In a similar fashion, the reaction of 5 with phosphite ligand generated Ru(σ-borate)(dihydridoborate) complex, 7, which is analogous to 6.
为了在不使用膦硼烷脱氢偶联剂的情况下建立硼 - 磷偶联反应，我们开发了一种新的合成方法，该方法使用第8族金属σ - 硼酸盐配合物[{κ - H,S,S'-BH L }Ru{κ - H,H,S - BH L}]（L = NC H S），即化合物1。用二苯基氯化膦（PPh Cl）处理化合物1得到1,5 - P,S螯合的钌二氢硼酸盐物种[PPh H{κ - H,H,S - BH(OH)L}Ru{κ - P,S-(Ph P)BH L}]，即化合物2。通过3c - 2e σ（Ru - H - B）键相互作用的断裂插入膦部分（PPh ）导致了硼 - 磷键的形成。在配合物2中，κ - P,S螯合的六元环呈船式构象。该杂环由所有不同的原子组成，这是杂原子环系统中最罕见的例子之一。理论结果展示了硼 - 磷偶联以及通过过渡金属实现稳定化的电子学见解。为了探索硼 - 磷键形成的另一条途径，我们进一步研究了化合物1和钌双（二氢硼酸盐）配合物5与仲氧化膦（SPO）的反应。虽然，化合物1与二苯基氧化膦的热解反应生成了类似的σ - 硼酸盐配合物3，但化合物5在室温下的类似反应导致形成了新型的含次膦（III）酸的Ru(σ - 硼酸盐)(二氢硼酸盐)配合物，即化合物6。以类似的方式，化合物5与亚磷酸酯配体的反应生成了Ru(σ - 硼酸盐)(二氢硼酸盐)配合物，即化合物7，它与化合物6类似。
