Photoracemization-Based Viedma Ripening of a BINOL Derivative

Area of Science:

• Organic Chemistry
• Stereochemistry
• Green Chemistry

Background:

• Viedma ripening is a key deracemization process for chiral molecules.
• It requires compounds to crystallize as conglomerates and be racemizable under crystallization conditions.
• Existing racemization methods for Viedma ripening are limited.

Purpose of the Study:

• To expand the scope of Viedma ripening by introducing a novel racemization method.
• To achieve successful deracemization of a chiral compound using UV-light-induced racemization.
• To demonstrate a new, cost-effective, and environmentally friendly approach to racemization.

Main Methods:

• Application of UV-light-induced racemization within a Viedma ripening process.
• Utilizing UV light and an organic base to promote excited-state proton transfer (ESPT) for racemization.
• Testing the method on a BINOL derivative that crystallizes as a conglomerate.

Main Results:

• Successful deracemization of a BINOL derivative using the novel UV-light-induced method.
• Demonstrated that UV light in combination with an organic base can induce racemization via ESPT.
• Validated the feasibility of integrating UV-light-induced racemization into Viedma ripening.

Conclusions:

• UV-light-induced racemization is a viable and effective new tool for Viedma ripening.
• This method broadens the applicability of Viedma ripening to more chiral compounds.
• The use of UV light offers a cheap and green catalytic source for racemization in chiral synthesis.