Two rhodamine derivatives: 9-[2-(ethoxycarbonyl)phenyl]-3,6-bis(ethylamino)-2,7-dimethylxanthylium chloride monohydrate and 3,6-diamino-9-[2-(methoxycarbonyl)phenyl]xanthylium chloride trihydrate

Abstract

The title compounds, C28H31N2O3(+)-Cl(-)-H2O (common name rhodamine-6g), (I), and C21H17N2O3(+)-Cl(-)-3H2O (common name rhodamine-123), (II), both have planar xanthene skeletons with a formal +1 charge on the amino N atoms delocalized through the pi-electron system so that the N-Csp(2) bond distances indicate significant double-bond character. The substituted planar phenyl groups make angles of 63.29 (8) and 87.96 (11) degrees with the xanthene planes in (I) and (II), respectively. In both molecules, the carbonyl bond vectors point toward the xanthene rings. The ethylamine groups in (I) are oriented similarly with their CH2-CH3 bond vectors pointing nearly perpendicular to the xanthene plane. The chloride ions and water molecules are disordered in both structures. In (I), the chloride ion and water molecule are disordered between two sites. One water and chloride alternately occupy the same site with occupancy factors of 0.5. The other 0.5-chloride and 0.5-water occupy two distinct positions separated by 0.747 (8) A. In (II), the chloride ion is disordered between three sites and one of the waters is disordered about two other sites. Both crystal structures are stabilized by hydrogen bonds involving the chloride ions, amino groups and water molecules, as well as by pi-pi stacking between xanthene planes.

Hydrogen properties in an organic molecule revealed by XFEL and electron crystallography

“…Total 48 and 38 rotation series for the rt and cryo datasets, respectively (numbers of datasets are written in the same manner below), were first ×2 binned, and processed with DIALS for indexing and integrating of diffraction spots. We found that the crystal form was different from that previously reported 19 . Reduced datasets were grouped and sorted by KAMO 42 , which carried out scaling and merging by using Pointless 43 , XSCALE 44 and BLEND 45 .…”

“…Extended Data Table 2), but different from the triclinic crystal structure with chlorine determined previously by XRD from a single crystal, in which the planes of the two rings are oblique to each other rather than normal 19 (Extended Data Fig. 2, f-h).…”

Lignin selective dyes: quantum-mechanical study of their characteristics

“…From the crystal data about the Acridine Orange cation (Obendorf et al 1976;Reddy et al 1979;Mattia et al 1984Mattia et al , 1995Kuban et al 1985;Gordon et al 2003), the Proflavine cation (Jones and Neidle 1975;Shieh et al 1980Shieh et al , 1982Swaminathan et al 1982;Aggarwal et al 1984;Ara and El Bahij 2004;Varga et al 2007), Methylene Blue (Marr et al 1973;Kahn-Harari et al 1973;Endres et al 1977;Snaathorst et al 1981;Enescu et al 2000;Sours et al 2002;Kavitha et al 2004;Li et al 2005;Soneta and Miyamura 2006;Raj et al 2007), Eosin (Harrison et al 2007), Rhodamine B (Fujii et al 1995;Nishikiori and Fujii 1997;Soneta et al 2006), Ethyl Rhodamine G (Wang et al 1997;Fun et al 1997;Liu et al 1998;Adhikesavalu et al 2001;Zhang et al 2001), Para-rosaniline (Koh and Eriks 1971;Liu et al 2002;Xie 2008), and Crystal Violet (Spangler et al 1989;Lovell et al 1999;Lacour et al 2002;Soneta et al 2006), as well as the substituted 1-phenyl-azo-2-naph...…”

Growth and optical properties of large single crystals of rhodamine from methanol solution

“…[8] consisting of Rh6G Á HCl Á H 2 O (names: 9-(2-carboxylatophenyl)-3,6-bis-(ethylamino)-2,7-dimethylxanthylium inner salt monohydrate, rhodamine 19 zwitterion, etc.) [7]. For the first time this possible photodegradation process is reported.…”