Unprecedented spin localisation in a metal-metal bonded dirhenium complex

he molecular and electronic structure of edge-sharing bioctahedral [N(n-Bu)4]3[Re2(mnt)5] is reported here. Despite the short intermetal bond length of 2.6654(2) Å with computed bond order of 1.2, the unpaired electron is localised by the asymmetric ligand distribution, as demonstrated by its remarkable EPR spectrum

Monoclinic form of 1,2,4,5-tetra­cyclo­hexyl­benzene

The mol­ecule of the title compound, C30H46, has a crystallographically imposed inversion center and the cyclo­hexyl groups are oriented with their methine H atoms pointing towards one another (H⋯H = 1.99 Å). The cyclohexyl groups adopt chair conformations. A significant C—H⋯π inter­action assembles mol­ecules into layers parallel to (100)

Ring Opening of Epoxides by Pendant Silanols

This document is the Accepted Manuscript version of a Published Work that appeared in final form in Organic Letters, copyright © 2022 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see doi.org/10.1021/acs.orglett.1c04310We present a new ring-opening reaction of epoxides by pendant silanols, catalyzed by either Ph3C+BF4– or BINOL-phosphoric acid. Silanol epoxides derived from trans-allylic alcohols, cis-allylic alcohols, trans-homoallylic alcohols, and cis-homoallylic alcohols were all compatible and gave products from either endo- or exo-ring opening. With silanol epoxides derived from 4-alkenyl silanols, an unusual rearrangement to tetrahydrofuran products was observed. The utility of this methodology was demonstrated in a short preparation of protected d-arabitol

Highly Regio- and Diastereoselective Tethered Aza-Wacker Cyclizations of Alkenyl Phosphoramidates

This document is the Accepted Manuscript version of a Published Work that appeared in final form in The Journal of Organic Chemistry, copyright © 2021 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.joc.1c01483.We present highly diastereoselective tethered aza-Wacker cyclization reactions of alkenyl phosphoramidates. “Arming” the phosphoramidate tether with 5-chloro-8-quinolinol was essential to achieving >20:1 diastereoselectivity in these reactions. The substrate scope with respect to alkenyl alcohols and phosphoramidate tether was extensively explored. The scalability of the oxidative cyclization was demonstrated, and the product cyclophosphoramidates were shown to be valuable synthons, including for tether removal. With chiral alkenyl precursors, enantiopure cyclic phosphoramidates were formed

Expanding the scope of ligand substitution from [M(S2C2Ph2] (M = Ni2+, Pd2+, Pt2+) to afford new heteroleptic dithiolene complexes

The scope of direct substitution of the dithiolene ligand from [M(S2C2Ph2)2] [M = Ni2+ (1), Pd2+ (2), Pt2+ (3)] to produce heteroleptic species [M(S2C2Ph2)2Ln] (n = 1, 2) has been broadened to include isonitriles and dithiooxamides in addition to phosphines and diimines. Collective observations regarding ligands that cleanly produce [M(S2C2Ph2)Ln], do not react at all, or lead to ill-defined decomposition identify soft σ donors as the ligand type capable of dithiolene substitution. Substitution of MeNC from [Ni(S2C2Ph2)(CNMe)2] by L provides access to a variety of heteroleptic dithiolene complexes not accessible from 1. Substitution of a dithiolene ligand from 1 involves net redox disproportionation of the ligands from radical monoanions, –S•SC2Ph2, to enedithiolate and dithione, the latter of which is an enhanced leaving group that is subject to further irreversible reactions

5-Hydr­oxy-1,7-bis­(1H-indol-3-yl)hepta-1,4,6-trien-3-one hemihydrate

The title compound, C23H18N2O2·0.5H2O, a derivative of the biologically active compound curcumin, crystallizes with two organic mol­ecules and a solvent water mol­ecule in the asymmetric unit. Each of the two independent mol­ecules is close to being planar (the dihedral angles between the indole ring systems are approximately 9 and 12°) and each exists in the keto–enol form. There is an intra­molecular O—H⋯O hydrogen bond between the keto and enol groups. In the crystal, the components interact by way of N—H⋯N, N—H⋯O and O—H⋯O hydrogen bonds

Crystal structure of ethyl 2-[2-((1E)-{(1E)-2-[2-(2-ethoxy-2-oxoethoxy)benzyl-idene]hydrazin-1-ylidene}methyl)phen-oxy]acetate

NSF–MRI grant No. 1228232 for the purchase of the diffractometer and Tulane University for support of the Tulane Crystallography Laboratory are gratefully acknowledged.Peer reviewedPublisher PD

A polymorph of tetra­ethyl­ammonium chloride

The structure of the title compound, C8H20N+·Cl−, is compared with a polymorph that was described earlier in the same space group. Differences in the conformations of the ethyl groups of the cation exist between the polymorphs. This study is given here in order to provide additional unit-cell data for use in qualitative identification of crystalline samples obtained in syntheses in which Et4N+·Cl− is either used or generated