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2-Hydroxyphenacyl ester: a new photoremovable protecting group.

ABSTRACT: A 2-hydroxyphenacyl moiety absorbing below 370 nm is proposed as a new photoremovable protecting group for carboxylates and sulfonates. Laser flash photolysis and steady-state sensitization studies show that the leaving group is released from a short-lived triplet state. In addition, DFT-based quantum chemical calculations were performed to determine the key reaction steps. We found that triplet excited state intramolecular proton transfer represents a major deactivation channel. Minor productive pathways involving the triplet anion and quinoid triplet enol intermediates have also been identified.

SUBMITTER: Ngoy BP

PROVIDER: S-EPMC3422872 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature

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2-Hydroxyphenacyl ester: a new photoremovable protecting group.

Ngoy Bokolombe Pitchou BP Sebej Peter P Solomek Tomáš T Lim Bum Hee BH Pastierik Tomáš T Park Bong Ser BS Givens Richard S RS Heger Dominik D Klán Petr P

Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology 20120706 9

A 2-hydroxyphenacyl moiety absorbing below 370 nm is proposed as a new photoremovable protecting group for carboxylates and sulfonates. Laser flash photolysis and steady-state sensitization studies show that the leaving group is released from a short-lived triplet state. In addition, DFT-based quantum chemical calculations were performed to determine the key reaction steps. We found that triplet excited state intramolecular proton transfer represents a major deactivation channel. Minor productiv ...[more]

PMID: 22766787

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