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The Remote Supergroup for Chemistry Undergraduates (RSCU) is a community of students and faculty from primarily undergraduate institutions that aims to (1) engage students in discussions of chemical research, (2) inform students of further educational and career pathways, (3) increase awareness and discourse of equity issues in science, and (4) foster scientific community across institutions. RSCU engaged participants in impactful virtual activities during the summer of 2020 when the COVID-19 pandemic precluded in-person undergraduate research experiences, and the program continued in 2021 as in-person research resumed. Results from self-reported surveys show that RSCU successfully achieved its aims both years, and both students and faculty research mentors benefited from participation. The diverse activities and scientific network cultivated by RSCU complement undergraduate research experiences and could be adapted to other disciplines. 

The crystal structures of ligand precursor bis(imidazolium) salts 1,1′-methylenebis(3- tert -butylimidazolium) dibromide monohydrate, C 15 H 26 N 4 + ·2Br − ·H 2 O or [ t Bu NHC 2 Me][Br] 2 ·H 2 O, 1,1′-(ethane-1,2-diyl)bis(3- tert -butylimidazolium) dibromide dihydrate, C 16 H 28 N 4 + ·2Br − ·2H 2 O or [ t Bu NHC 2 Et][Br] 2 ·2H 2 O, 1,1′-methylenebis[3-(2,4,6-trimethylphenyl)imidazolium] dibromide dihydrate, C 25 H 30 N 4 2+ ·2Br − ·2H 2 O or [ Mes NHC 2 Me][Br] 2 ·2H 2 O, and 1,1′-(ethane-1,2-diyl)bis[3-(2,4,6-trimethylphenyl)imidazolium] dibromide tetrahydrate, C 26 H 32 N 4 2+ ·2Br − ·4H 2 O or [ Mes NHC 2 Et][Br] 2 ·4H 2 O, are reported. At 293 K, [ t Bu NHC 2 Me][Br] 2 ·H 2 O crystallizes in the P 2 1 / c space group, while [ t Bu NHC 2 Et][Br] 2 ·2H 2 O crystallizes in the P 2 1 / n space group at 100 K. At 112 K, [ Mes NHC 2 Me][Br] 2 ·2H 2 O crystallizes in the orthorhombic space group Pccn while [ Mes NHC 2 Et][Br] 2 ·4H 2 O crystallizes in the P 2 1 / c space group at 100 K. Bond distances and angles within the imidazolium rings are generally comparable among the four structures. All four bis(imidazolium) salts co-crystallize with one to four molecules of water. 

Two cis -dioxomolybdenum complexes based on salan ligands with different backbones are reported. The first complex, dioxido{2,2′-[l,2-phenylenebis(iminomethylene)]bis(phenolato)}molybdenum(VI) dimethylformamide disolvate, [Mo(C 20 H 18 N 2 O 2 )O 2 ]·2C 3 H 7 NO ( Ph LMoO 2 , 1b ), features a phenyl backbone, while the second complex, (6,6′-{[(cyclohexane-1,2-diyl)bis(azanediyl)]bis(methylene)}bis(2,4-di- tert -butylphenolato))dioxidomolybdenum(VI) methanol disolvate, [Mo(C 36 H 56 N 2 O 2 )O 2 ]·2CH 3 OH ( Cy LMoO 2 , 2b ), is based on a cyclohexyl backbone. These complexes crystallized as solvated species, 1b ·2DMF and 2b ·2MeOH. The salan ligands Ph LH 2 ( 1a ) and Cy LH 2 ( 2a ) coordinate to the molybdenum center in these complexes 1b and 2b in a κ 2 N ,κ 2 O fashion, forming a distorted octahedral geometry. The Mo—N and Mo—O distances are 2.3475 (16) and 1.9567 (16) Å, respectively, in 1b while the corresponding measurements are Mo—N = 2.3412 (12) Å, and Mo—O = 1.9428 (10) Å for 2b . A key geometrical feature is that the N—Mo—N angle of 72.40 (4)° in Cy LMoO 2 is slightly less than that of the Ph LMoO 2 angle of 75.18 (6)°, which is attributed to the flexibility of the cyclohexane ring between the nitrogen as compared to the rigid phenyl ring in the Ph LMoO 2 . 

The structure of a trinuclear zinc complex, hexakis(μ 2 -2-anilinobenzoato)diaquatrizinc(II), [Zn 2 (C 13 H 10 NO 2 ) 6 (H 2 O) 2 ] or (NPA) 6 Zn 3 (H 2 O) 2 (NPA is 2-anilinobenzoate or N -phenylanthranilate), is reported. The complex crystallizes in the triclinic space group P -1 and the central Zn II atom is located on an inversion center. The NPA ligand is found to coordinate via the carboxylate O atoms with unique C—O bond lengths that support an unequal distribution of resonance over the carboxylate fragment. The axial H 2 O ligands form hydrogen bonds with neighboring molecules that stabilize the supramolecular system in rigid straight chains, with an angle of 180° along the c axis. π stacking is the primary stabilization along the a and b axes, resulting in a highly ordered supramolecular structure. Docking studies show that this unique supramolecular structure of a trinuclear zinc complex has potential for binding to the main protease (M pro ) in SARS-CoV-2 in a different location from Remdesivir, but with a similar binding strength. 

The Remote Supergroup for Chemistry Undergraduates (RSCU) brought together student and faculty scientists from 18 public and private institutions that primarily serve undergraduates, spanning 14 US states and one other country. RSCU’s goals included networking across institutions, promoting student understanding of the chemical literature, informing students about further educational and career opportunities, and facilitating discussions of equity and inclusion in science. 

The title compound, bis(1,2-diphenyl-2-sulfanylideneethanethiolato-κ 2 S , S ′)(1,3,5-triaza-7-phosphaadamantane-κ P )cobalt(II) dichloromethane hemisolvate, [Co(pdt) 2 (PTA)]·0.5C 2 H 4 Cl 2 or [Co(C 14 H 10 S 2 ) 2 (C 6 H 12 N 3 P)]·0.5C 2 H 4 Cl 2 , contains two phenyldithiolene (pdt) ligands and a 1,3,5-triaza-7-phosphaadamantane (PTA) ligand bound to cobalt with the solvent 1,2-dichloroethane molecule located on an inversion center. The cobalt core exhibits an approximately square-pyramidal geometry with partially reduced thienyl radical monoanionic ligands. The supramolecular network is consolidated by hydrogen-bonding interactions primarily with nitrogen, sulfur and chlorine atoms, as well as parallel displaced π-stacking of the aryl rings. The UV–vis, IR, and CV data are also consistent with monoanionic dithiolene ligands and an overall Co II oxidation state.