Carbocations, which are positively charged highly electrophilic intermediates, are efficacious for the direct alkylation of low-reactive nucleophiles. The utilization of carbocations in S_N1 reactions relies on the activation of their precursors in the presence of a nucleophile. However, undesirable interactions between the nucleophile and the leaving group activator limit the scope of acceptable nucleophiles. Here we report a strategy to conduct S_N1 reactions involving unstable carbocations in an alternative stepwise procedure, which was demonstrated by the benzylation of various neutral nucleophiles. In the first step, carbocations were accumulated in a nucleophile-free solution in the form of carbocationoids utilizing the coordinative stabilization of triazinediones. Subsequently, the addition of these solutions in the second step enabled room-temperature alkylation without the need for acidic additives. This methodology overcomes the inherent challenges of carbocations in S_N1 reactions.

碳阳离子是带正电荷的高亲电中间体，可有效用于低反应性亲核试剂的直接烷基化。_{S N} 1 反应中碳阳离子的利用依赖于其前体在亲核试剂存在下的活化。然而，亲核试剂和离去基团活化剂之间不期望的相互作用限制了可接受的亲核试剂的范围。在这里，我们报告了一种在替代逐步程序中进行涉及不稳定碳阳离子的S _{N 1 反应的策略，该策略通过各种中性亲核试剂的苄基化得到了证明。}第一步，利用三嗪二酮的配位稳定作用，碳阳离子以碳阳离子的形式积累在无亲核试剂的溶液中。随后，在第二步中添加这些溶液能够在不需要酸性添加剂的情况下进行室温烷基化。_{该方法克服了 S N} 1 反应中碳阳离子的固有挑战。