Light-Sensitive Protecting Groups for Amines and Alcohols: The Photosolvolysis of N-Substituted 7-Nitroindolines

Alfred Hassner; Diana Yagudayev; Tarun K. Pradhan; Abraham Nudelman; Boaz Amit

doi:10.1055/s-2007-985580

LETTER

Light-Sensitive Protecting Groups for Amines and Alcohols: The Photosolvolysis of N-Substituted 7-Nitroindolines

Alfred Hassner*^a, Diana Yagudayev^a, Tarun K. Pradhan^a, Abraham Nudelman^a, Boaz Amit^b
^a Department of Chemistry, Bar-Ilan University, Ramat-Gan 52900, Israel
Fax: +972(3)7384053; e-Mail: hassna@mail.biu.ac.il;
^b ProChon Biotech Ltd., Weizmann Science Park, Nes Ziona, 70400, Israel

Abstract

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Abstract

Representative examples of primary and secondary amines were protected as urea derivatives 4 of 5-bromo-7-nitroindoline and even more efficiently as ureas 8 derived from 5,7-dinitroindoline, via high-yield reactions with carbamoyl chlorides 3 and 7, respectively. Deprotection of 4 or 8 was achieved in high yields by UV irradiation at room temperature in Pyrex vessels under neutral conditions and exclusion of air. In a similar manner the dinitroindolines serve as protecting groups for alcohols and phenols; the derived carbamates 5 and 9 can likewise be deprotected photochemically in high yields.

Key words

alcohols - amines - protecting groups - photochemistry - ureas - carbamates - indolines

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References

References and Notes

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