Saturated Five-Membered Ring Azaheterocyclic Spiropyrans

SATURATED FIVE-MEMBERED RING AZAHETEROCYCLIC SPIROPYRANS 

For 105 ongoing from benzo-condensed (see Table 10) to a simple saturated heterocycle ring 111, it may be seen that the absence of the benzo group on the heterocyclic moiety leads to a hypsochromic shift of the absorption maximum of the merocyanine form, although the colorability is not gready affected (Table 11). 

Tahtc if). Subsiiiucnt Efleets on the Photodcgradaiiim of IJonawjj ihcienjcyctie Spirepyrans in Toluene at 25 

The introduction of a C2HS group at C3 does not affect degradation whereas a phenyl group at this position improves photostability (112, 113, and 114). Compared to the indoline series, the pyrrolidine spiropyrans offer no special advantages. 

Titbit 11. Substituent Effects on the Photodcgradaiion of Five-Metnbered Satumtii Ar-ahclcrocyrtic Spiropyrans in Toluene (5 10 5f unless Otherwise Indicated) at 

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SATURATED FIVE-MEMBERED RING AZAHETEROCYCLIC SPIROPYRANS... 

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