Rapid electrocyclization is proposed under radical anionic conditions in organic photochromes. DFT calculations have been performed to investigate the radical anion mediated electrocyclization in different organic photochromes. Furthermore, the activation barriers under radical anionic conditions are compared with those in neutral and radical cationic conditions. The nuclear independent chemical shift (NICS(0)) and synchronicity calculations have been performed for the confirmation of concerted nature and aromatic character of transition states, respectively. The activation barrier for thermal return of cyclophanediene (CPD) to dihydropyrene (DHP) under radical anionic conditions is very lower (ΔH = 5.92 kcal/mol, ΔG = 6.97 kcal/mol) than under neutral conditions, but higher than that in radical cationic conditions (ΔH = 3.13 kcal/mol, ΔG = 4.0 kcal/mol). Similarly, the other prominent classes of photochromes; dithienylethene (ΔH = 20.12 kcal/mol, ΔG = 21.55 kcal/mol) and vinylheptafulvene (ΔH = 23.72 kcal/mol, ΔG = 24.82 kcal/mol) have shown decreased activation barrier under radical anionic condition. However, activation barrier of fulgide under radical anionic conditions is not different than those under neutral and radical cationic conditions. Synchronicity and NICS(0) values for organic photochromes also show significant changes under radical anionic conditions.

提出在自由基阴离子条件下在有机光致变色剂中进行快速电环化。已经进行了DFT计算以研究自由基阴离子介导的不同有机光致色素中的电环化。此外，将自由基阴离子条件下的活化势垒与中性和自由基阳离子条件下的活化势进行了比较。进行了核独立化学位移（NICS（0））和同步计算，分别用于确认过渡态的一致性质和芳香特性。自由基阴离子条件下环戊二烯（CPD）热返回二氢py（DHP）的活化势垒比中性条件下低（ΔH= 5.92 kcal / mol，ΔG= 6.97 kcal / mol），但高于自由基阳离子型条件（ΔH= 3.13 kcal / mol，ΔG= 4。0 kcal / mol）。同样，其他主要的彩色显色剂；二噻吩乙烯（ΔH= 20.12 kcal / mol，ΔG= 21.55 kcal / mol）和乙烯基七氟乙烯（ΔH= 23.72 kcal / mol，ΔG= 24.82 kcal / mol）在自由基阴离子条件下显示出降低的活化势垒。但是，在自由基阴离子条件下，g灭肽的激活势垒与在中性和自由基阳离子条件下的激活势垒没有什么不同。有机自由基的同步性和NICS（0）值在自由基阴离子条件下也显示出显着变化。激肽在自由基阴离子条件下的活化势垒与中性和自由基阳离子条件下的活化势垒没有区别。有机自由基的同步性和NICS（0）值在自由基阴离子条件下也显示出显着变化。激肽在自由基阴离子条件下的活化势垒与中性和自由基阳离子条件下的活化势垒没有区别。有机自由基的同步性和NICS（0）值在自由基阴离子条件下也显示出显着变化。