Viedma ripening is ad eracemizationp rocess that has been used to deracemize ar ange of chiral molecules. The method hast wo major requirements:t he compound needs to crystallize as ac onglomerate and it needs to be racemizable under the crystallization conditions. Although conglomerate formation can be induced in different ways, the number of racemization methods is still ratherl imited. To extend the scope of Viedma ripening, in the present research we applied UV-light-induced racemization in a Viedmar ipening process, and report the successful deracemizationo faB INOL derivative crystallizing as ac onglomerate. Irradiation by UV light activatest he target compound in combination with an organic base, required to promote the excited-state proton transfer (ESPT), leadingt hereaftert o racemization. This offers an ew tool towards the development of Viedma ripening processes, by using ac heap and "green"c atalytic source like UV light to racemize suitable chiral compounds.

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Viedma deracemization is based on solution phase racemization, dissolution of racemic or scalemic conglomerates and crystal growth through autocatalytic cluster formation. With rate limiting racemization, its acceleration by appropriate catalysts may result in speeding up deracemization. A conglomerate‐forming chiral compound may principally racemize directly, or via reverse of its formation reaction. For a hydrazine derivative, we investigated available racemization pathways in presence of pyrrolidine or thiourea amine as base catalysts: via Mannich or aza‐Michael reaction steps and their reverse, or by enolization. Racemization by enolization was computationally found to dominate, both under water‐free conditions and in presence of water, involving a multitude of different pathways. Faster racemization in presence of water resulted indeed in more rapid deracemization, when the base was pyrrolidine. Under water‐free conditions, the role of water as enolization catalyst is assumed by chiral hydrazine itself – in autocatalytic racemization and in which both reactant and product are catalysts.

Cannabichromene (CBC, 1a) occurs in Cannabis (Cannabis sativa) as a scalemate having a composition that is strain-dependent in terms of both enantiomeric excess and enantiomeric dominance. In the present work, the chirality of CBC (1a), a noncrystalline compound, was shown not to be significantly affected by standard conditions of isolation and purification, and enantiomeric self-disproportionation effects were minimized by carrying out the chiral analysis on crude fractions rather than on purified products. A genetic basis for the different enantiomeric state of CBC in Cannabis therefore seems to exist, implying that the chirality status of natural CBC (1a) in the plant is associated with the differential expression of CBCA-synthase isoforms and/or of associated directing proteins with antipodal enantiospecificity. The biological profile of both enantiomers of CBC should therefore be investigated independently to assess the contribution of this compound to the activity of Cannabis preparations.