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| Untersuchte Arbeit: Seite: 41, Zeilen: 8-15 |
Quelle: Pillai 1980 Seite(n): 2, Zeilen: left col. 6-18 |
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| Another important factor to be considered in the selection of a photosensitive masking group is the lifetime of the excited species that is responsible for the particular photoreaction. Thus, if the protected substrate has a long excited state lifetime before cleavage occurs, the chances for undesirable quenching processes to reduce the efficiency of the cleavage reaction are greater.
This would hinder the removal of the protecting group and also might labilise the quenching species such energy dissipation processes might result in some undesired changes in the substrate. Therefore, it would seem a distinct advantage to design a protecting group with a chromophore characterized by a short-lived excited state. |
The lifetime of the excited state that is responsible for the deprotection reaction is of great significance. If the protected substrate has a long excited state lifetime before cleavage occurs the chances for undesirable quenching processes to reduce the efficiency of the cleavage reaction are greater. This fact would hinder the removal of the protecting group and also might labilise the quenching species. Thus, such energy dissipation processes might result in some undesired changes in the substrate. Therefore, it would seem a distinct advantage to have a protecting group with a short-lived excited state. |
No source given; though nearly identical nothing has been marked as a citation. |
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