Photochemically-induced C-C bond formation between tertiary amines and nitrones
Kennosuke Itoh1, Ryo Kato, Daito Kinugawa
1Department of Medicinal Chemistry, School of Pharmacy, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan. itok@pharm.kitasato-u.ac.jp.
Organic & Biomolecular Chemistry
|July 25, 2015
Summary
This study demonstrates that photoexcited nitrones can functionalize tertiary amines, yielding β-amino hydroxylamines through direct C-H activation. Organophotosensitizers accelerate these reactions, enabling efficient synthesis with high selectivity.
Area of Science:
- Organic Chemistry
- Photochemistry
- Synthetic Methodology
Background:
- Nitrones are versatile reagents in organic synthesis.
- Tertiary amines can undergo C-H functionalization.
- Photochemical methods offer unique reactivity pathways.
Purpose of the Study:
- To develop a novel method for synthesizing β-amino hydroxylamines.
- To achieve direct sp(3) C-H functionalization of tertiary amines using nitrones.
- To explore the use of organophotosensitizers in accelerating these reactions.
Main Methods:
- Utilizing photoexcited nitrones as electron and radical acceptors.
- Employing tertiary amines as substrates for C-H functionalization.
- Leveraging organophotosensitizers and photoirradiation to promote reactions.
- Investigating regioselective and diastereoselective radical generation and addition.
Main Results:
- Successful synthesis of β-amino hydroxylamines in good yields.
- Demonstration of photochemically-induced direct sp(3) C-H functionalization of tertiary amines.
- Achieved highly regioselective generation of primary α-aminoalkyl radicals.
- Observed diastereoselective addition reactions of radicals with nitrones.
- Performed highly diastereoselective reactions with chiral nitrones.
Conclusions:
- Photoexcited nitrones are effective in the direct C-H functionalization of tertiary amines.
- Organophotosensitizer-mediated photochemistry provides an efficient route to β-amino hydroxylamines.
- The methodology allows for high regioselectivity and diastereoselectivity in radical reactions.
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