Electronic Supporting Information NMR Crystallography of L ...€¦ · NMR Crystallography of L-Arginine: Disentangling Crystallographic Inequivalence and Polymorphism by One- and

Electronic Supporting Information

NMR Crystallography of L-Arginine: Disentangling Crystallographic Inequivalence and Polymorphism by One- and Two-Dimensional Solid-State NMR Spectroscopy

Jose-Enrique Herbert-Puchetaa, b, c, Henri Colaux a, b, c, Geoffrey Bodenhausena, b, c and Piotr Tekely *,a ,b, c a Ecole Normale Supérieure, Département de Chimie, 24 rue Lhomond, 75005 Paris, France b Université Pierre-et-Marie Curie, Place Jussieu, 75005 Paris, France c CNRS, UMR 7203, Département de Chimie, 24 rue Lhomond, 75005 Paris, France Figure S1. Expansions of the 13C CP/MAS spectrum of L-arginine (sample 1). The resonance lines belonging to the two individual polymorphs, separated by proton relaxation editing, are highlighted in red and blue.

L-arginine HCl•H20 L-arginine HCl

13C isotropic chemical shift

Figure S2. Expansions of J-splitting patterns due to J(13C, 13C) for C’ and all aliphatic carbons as well as J(13C, 15N) for Cζ carbon in a 13C CP/MAS spectrum of L-arginine (sample 1). The scalar splittings of the resonance lines of individual polymorphs are highlighted in red and blue.

Figure S3. Expansions of J-splitting patterns due to J(13C, 15N) in a 15N CP/MAS spectrum of L-arginine (sample 1). The scalar splittings of the resonance lines from individual polymorphs are highlighted in red and blue.

Figure S4. Expansion of a 2D 13C-13C correlation spectrum of sample 1 for the Cζ and Cδ resonances. The correlations within individual polymorphs are highlighted in red and blue.

Figure S5. Expansion of a 2D 13C- 15N correlation spectrum of sample 1 for Cδ and Nε resonances.

Figure S6. (bottom) High- and low-field regions of a natural abundance 13C CP/MAS spectrum of anhydrous L-arginine HCl (sample 3). (top) Natural abundance 13C CP/MAS spectrum of L-arginine HCl monohydrate obtained from the recrystallisation of sample 3 using the pair solvent method: 200mg of sample 3 were dissolved in 0.8 mL of a 1:1 ethanol-water mixture at 40oC as described by Dow et al.(8c). After complete dissolution, the solution was cooled down using an external ice bath. A crystalline precipitate was obtained when 2 mL of concentrated acetone (99%) were added to the cooled L-arginine solution. To promote a better and faster crystallisation of L-arginine HCl monohydrate, it was necessary to scratch the flask’s wall as acetone was being added. High vacuum filtration of the crystalline precipitate was carried out, washing the product with cold acetone. Note the presence of a residual fraction (<10%) of anhydrous L-arginine HCL.

Figure S7. T1(13C) relaxation data obtained by standard T1CP method. Solid lines stem from the double-exponential fitting.

Table S1. T1 (13C)* relaxation times (in seconds) for carbons in sample 1. The ratio (%) was obtained from the pre-exponential factors of corresponding exponential functions.

L-arginine HCl⋅Η 2Ο L-arginine HCl Ratio (%)

C’ 32.8 268.2 (77:23)

Cα 33.6 295.8 (65:35)

Cβ 33.7 288 (63:37)

Cγ 34.3 284.9 (62:38)

Cδ 33.2 276.4 (63:37)

Cζ 45.2 400.1 (75:25)

*± 10 %