Synthesis, resolution and crystal structures of two enanti-omeric rhodamine derivatives.
The title mol-ecule,rac-6'-bromo-3'-di-ethyl-amino-3H-spiro-[2-benzo-furan-1,9'-xanthen]-3-one, C24H20BrNO3, was synthesized and the two enanti-omers which formed were separated. The structures of all three compounds were determined and compared with those of a variety of related derivatives. A notable feature is the fold of the xanthene portion which ranges from 15.15 (13)° in the racemate to 2.42 (2)° in one mol-ecule of theRenanti-omer with that for theSenanti-omer having an inter-mediate value. The differences are attributed to the number and severity of inter-molecular inter-actions which include C-H⋯O hydrogen bonds, C-H⋯π(ring) and, in theSenanti-omer, a π-stacking inter-action between the carbonyl group and an aromatic ring.
Department of Chemistry, Loyola University, New Orleans, LA 70118, USA.
Clifton J
CJ
Stephenson
Department of Chemistry, Tulane University, New Orleans, LA 70118, USA.
Joel T
https://orcid.org/0000-0003-3488-1945
JT
Mague
Department of Chemistry, Loyola University, New Orleans, LA 70118, USA.
Nathaniel
N
Kamm
Department of Chemistry, Loyola University, New Orleans, LA 70118, USA.
Nathalie
N
Aleman
Department of Chemistry, Loyola University, New Orleans, LA 70118, USA.
Dayla
D
Rich
Department of Chemistry, Loyola University, New Orleans, LA 70118, USA.
Quynh-Nhu
QN
Dang
Department of Chemistry, Loyola University, New Orleans, LA 70118, USA.
Ha Van
HV
Nguyen
chiral sensors; crystal structure; hydrogen bond; rhodamine; xanthene