TaMCF silicas modified with alkaline metals can be considered a novel family of highly efficient bifunctional catalysts involved in the synthesis of chromene derivatives, from salicylaldehyde 2 and acetonitrile compounds, under mild conditions, showing enhanced catalytic performance than their NbMCF analogues. The observed reactivity was mainly attributed to the higher basicity of the Me/TaMCF but also the texture of the samples. The Me/TaMCF silicas showed higher Brønsted basicity than the Nb ones as indicated by the stronger interaction between alkali metals and Ta in the UV–vis and the test reaction experiments.

On the other hand, the basicity of Me/TaMCF together the reactivity degree and steric hindrance of the starting acetonitriles are key factors influencing the reaction selectivity. In conclusion, the basicity of the samples plays an important role initiating the reaction by activation of nucleophile but also a compromise between alkaline cation size and basicity is required.

用碱金属改性的TaMCF二氧化硅被认为是新型的高效双功能催化剂家族，参与在温和条件下由水杨醛2和乙腈化合物合成色烯衍生物，显示出比其NbMCF类似物更高的催化性能。观察到的反应性主要归因于Me / TaMCF的较高碱性，但也归因于样品的质地。Me / TaMCF二氧化硅显示出比Nb更高的布朗斯台德碱度，这是由碱金属和Ta在紫外可见光下的较强相互作用以及测试反应实验所表明的。

另一方面，Me / TaMCF的碱性，起始乙腈的反应度和位阻是影响反应选择性的关键因素。总之，样品的碱度在通过亲核试剂的活化引发反应中起着重要的作用，但是也需要在碱性阳离子的大小和碱度之间进行折衷。