Abstract
The title compound I, C13H10N2O2S2, crystallizes in the monoclinic space group C2/c with eight mol-ecules in the unit cell. Excluding for the ethyl substituent, the mol-ecule of I adopts a nearly coplanar conformation (r.m.s. deviations is 0.058 Å), which is supported by the intra-molecular C-H⋯O hydrogen-bonding inter-action between the two ring systems [C⋯O = 2.859 (3) Å]. In the crystal, the mol-ecules form dimeric associates via two bifurcated C-H⋯O hydrogen-bonding inter-actions between an ene hydrogen atom and a carbonyl functional group of an adjacent mol-ecule [C⋯O = 3.133 (3) Å] and vice versa. The crystal structure is further stabilized by a three-dimensional network of weak hydrogen bonds between one mol-ecule and six adjacent mol-ecules as well as offset π-π stacking. The combination of the quinoxaline 2(1H)-one moiety with the di-thio-carbonate moiety extends the aromaticity of the quinoxaline scaffold towards the substituent as well as influencing the π-system of the quinoxaline. The title compound is the direct precursor for a di-thiol-ene ligand mimicking the natural cofactor ligand molybdopterin.
Highlights
The title compound I, C13H10N2O2S2, crystallizes in the monoclinic space group C2/c with eight molecules in the unit cell
This planitarity is supported by intramolecular hydrogen bonding between the dithiolene hydrogen atom and the quinoxaline carbonyl oxygen atom [C2—H2Á Á ÁO2 with DÁ Á ÁA = 2.859 (3) A ; Table 1]
The C O bond [1.212 (3) A ] of the carbonodithioate moiety is slightly shorter than the carbonyl C O bond [1.232 (3) A ] of the quinoxaline substituent, suggesting that the latter might be involved to a small extent in resonance effects of the -system, whereas the former is not
Summary
Non-innocent dithiolenes and their role as interesting ligand systems were discovered in the early 1960s. Mpt is present in most molybdenum enzymes and all tungsten enzymes and binds the respective central metal by a dithiolene moiety. The target dithiolene ligand replicates the pyrazine moiety of mpt in its half-reduced form and in addition contains an oxofunction in the position of the pyran ring of the natural product. Symmetry codes: (i) Àx; Ày þ 2; Àz þ 1; (ii) x; Ày þ 1; z þ 12; (iii) Àx þ 12; Ày þ 12; Àz þ 1; (iv) x; y À 1; z
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Acta crystallographica. Section E, Crystallographic communications
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
