Issue 14, 2021

Ambient l-lactic acid crystal polymorphism

Abstract

Only one crystalline phase of the metabolite, L-lactic acid (LLA), has been described since its isolation from sour milk as long ago as 1780. Herein, we report the structures of two new crystalline polymorphs of LLA obtained from supercooled melts and characterized by X-ray diffraction and micro-Raman spectroscopy, as well as their transformations from one phase to another. None of the three crystal structures are consistent with the aggregate geometries of LLA in cold matrices, in solution, or those predicted by quantum chemical computations. The latter aggregates feature typical cyclic carboxylic acid dimers not represented in any of the crystal structures. These differences underscore the difficulty of reasoning solid state structure from associations in other media.

Graphical abstract: Ambient l-lactic acid crystal polymorphism

Supplementary files

Article information

Article type
Communication
Submitted
27 fev 2021
Accepted
23 mar 2021
First published
23 mar 2021

CrystEngComm, 2021,23, 2644-2647

Author version available

Ambient L-lactic acid crystal polymorphism

J. Yang, C. T. Hu, E. Reiter and B. Kahr, CrystEngComm, 2021, 23, 2644 DOI: 10.1039/D1CE00285F

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements