Is the phosphaethynolate anion, (OCP)−, an ambident nucleophile? A spectroscopic and computational study
作者:Dominikus Heift、Zoltán Benkő、Hansjörg Grützmacher
DOI:10.1039/c3dt53569j
日期:——
The reactivity of Na(OCP) was investigated towards triorganyl compounds of the heavier group 14 elements (R3EX R = Ph or iPr; E = Si, Ge, Sn, Pb; X = Cl, OTf). In the case of E = Si two constitutional isomers were formed and characterised in situ: R3SiâOâCP is the kinetic and R3SiâPCO is the thermodynamic product, representing experimental evidence of the ambident character of the (OCP)â anion. Applying theoretical calculations and spectroscopic methods, the compound previously reported as iPr3SiâOâCP can now unambiguously be identified as iPr3SiâPCO. The heavier analogues form exclusively the phosphaketene isomer R3EâPCO (E = Ge, Sn, Pb). DFT calculations were performed to gain deeper insight into the bonding and thermodynamic stability of these compounds.
对Na(OCP)与较重第14族元素的三有机化合物(R3EX R = Ph或iPr; E = Si, Ge, Sn, Pb; X = Cl, OTf)的反应性进行了研究。在E = Si的情况下,形成了两种构造异构体并进行了原位表征:R3Si-O-CP是动力学产物,R3Si-PCO是热力学产物,代表了(OCP)⁻阴离子的双位特性的实验证据。应用理论计算和光谱方法,先前报道的化合物iPr3Si-O-CP现在可以明确地被鉴定为iPr3Si-PCO。较重的类似物仅形成磷卡烯异构体R3E-PCO(E = Ge, Sn, Pb)。进行了DFT计算,以深入了解这些化合物的键合和热力学稳定性。