Infrared (IR) excitation of vibrations that participate in the reaction coordinate of an otherwise thermally driven chemical reaction are believed to lead to its acceleration. Attempts at the practical realization of this concept have been hampered so far by competing processes leading to sample heating. Here we demonstrate, using femtosecond IR-pump IR-probe experiments, the acceleration of urethane and polyurethane formation due to vibrational excitation of the reactants for 1:1 mixtures of phenylisocyanate and cyclohexanol, and toluene-2,4-diisocyanate and 2,2,2-trichloroethane-1,1-diol, respectively. We measured reaction rate changes upon selective vibrational excitation with negligible heating of the sample and observed an increase of the reaction rate up to 24%. The observation is rationalized using reactant and transition-state structures obtained from quantum chemical calculations. We subsequently used IR-driven reaction acceleration to write a polyurethane square on sample windows using a femtosecond IR pulse.

参与其他方式热驱动化学反应的反应坐标的振动的红外（IR）激发会导致其加速。迄今为止，由于导致样品加热的竞争过程，阻碍了这一概念的实际实现的尝试。在这里，我们使用飞秒IR泵IR探针实验证明了苯异氰酸酯和环己醇1：1混合物，甲苯2,4-二异氰酸酯和2,2的混合物对反应物的振动激发而加速了聚氨酯和聚氨酯的形成，2-三氯乙烷-1，1-二醇。我们测量了选择性振动激发下样品的可忽略不计的加热下的反应速率变化，并观察到反应速率最多提高了24％。使用从量子化学计算获得的反应物和过渡态结构来合理化观察。随后，我们使用飞秒IR脉冲，通过IR驱动的反应加速在样品窗口上写了一个聚氨酯正方形。