A heterofunctional ligand approach for the preparation of high connectivity coordination polymers: combining a “bridge” and “pillar” in one ligand

Two of the most successful strategies for the preparation of three-dimensional coordination polymers and MOFs are reticular synthesis and pillaring. Here we present a new approach which combines aspects of both of these by employing a heterofunctional dicarboxylic and dipyridyl ligand, 2,5-di(pyridin-4-yl)terephthalic acid (H2L). The reaction of H2L with zinc(II) produces a non-interpenetrated 3D coordination polymer [ZnL(H2O)]n

Main Group Tellurium Heterocycles Anchored by a (P2N2)-N-V Scaffold and Their Sulfur/Selenium Analogues

A comprehensive investigation of reactions of alkali-metal derivatives of the ditelluro dianion [TePV((NBu)-Bu-t)(mu-(NBu)-Bu-t)](2)(2-) (L2-, E = Te) with p-block element halides produced a series of novel heterocycles incorporating (P2N2)-N-V rings, tellurium, and group 13-16 elements. The dianion engages in Te,Te'-chelation to the metal center in Ph2Ge and R2Sn (R = Bu-t, Bu-n, Ph) derivatives; similar behavior was noted for group 14 derivatives of L2- (E = S, Se). In the case of group 13 trihalides MCl3 (M = Ga, In), neutral spirocyclic complexes (L)M[(NBu)-Bu-t(Te)P-v(mu-(NBu)-Bu-t)(2)(PN)-N-III(H)Bu-t)] (M = Ga, In) comprised of a Te,Te'-chelated ligand L2- and a N,Te-bonded ligand resulting from loss of Te and monoprotonation were obtained. In reactions with RPCl2 (R = Bu-t, Ad, (Pr2N)-Pr-i) a significant difference was observed between Se- and S-containing systems. In the former case, Se,Se'-chelated derivatives were formed in high yields, whereas the N,S-chelated isomers predominated for sulfur. All complexes were characterized by multinudear (H-1, P-31, Se-77, Sn-119, and Te-123) NMR spectroscopy; this technique was especially useful in the analysis of the mixture of (L) (Se) and (L)(SeSe) obtained from the reaction of Se2Cl2 with L2- (E = Te). Single-crystal X-ray structures were obtained for the spirocydic In complex (9), (L)GePh2 (E = Te, 10), (L)(SnBu2)-Bu-t = Te, 12a); E = Se, 12aSe, E = S, 12aS) and (L)(mu-SeSe) (E = Te, 16)

Correction: Straightening out halogen bonds (CrystEngComm (2020) 22 (1687–1690) DOI: 10.1039/D0CE00176G)

The authors regret an error in eqn (1) of the published manuscript. The correct equation is: [formul presented]. Furthermore, the definition of type α halogen bonds should also read: 0.9 ≥ ψ ≥ 1 The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers

1,4-Diazacubane crystal structure rectified as piperazinium

All 21 [n]-azacubanes are proposed by theoreticians to be stable, however, to-date only the synthesis of 1,4-diazacubane has been reported – as a Ni2+ templated Kagome metal organic framework (MOF). Described herein is the structural reassignment of this Kagome MOF on the basis of deducing the precise experimental procedure, and demonstrating that rather than the formation of 1,4-diazacubane, charge is balanced by disordered piperazinium cations across a twelve-fold symmetry site. Furthermore, quantum chemical calculations reveal that 1,4-diazacubane is unlikely to form under the reported conditions due to unfavorable enthalpies for select hypothetical reactions leading to such a product. This significant structure correction upholds the unconquered synthesis status quo of azacubane

Main Group Tellurium Heterocycles Anchored by a P₂^VN₂ Scaffold and Their Sulfur/Selenium Analogues

A comprehensive investigation of reactions of alkali-metal derivatives of the ditelluro dianion [TeP^V(N^tBu)­(μ-N^tBu)]₂^2– (<b>L</b>^2–, E = Te) with p-block element halides produced a series of novel heterocycles incorporating P₂^VN₂ rings, tellurium, and group 13–16 elements. The dianion engages in Te,Te′-chelation to the metal center in Ph₂Ge and R₂Sn (R = ^tBu, ⁿBu, Ph) derivatives; similar behavior was noted for group 14 derivatives of <b>L</b>^2– (E = S, Se). In the case of group 13 trihalides MCl₃ (M = Ga, In), neutral spirocyclic complexes (<b>L</b>)­M­[N^tBu­(Te)­P^V(μ-N^tBu)₂P^IIIN­(H)^tBu)] (M = Ga, In) comprised of a Te,Te′-chelated ligand <b>L</b>^2– and a N,Te-bonded ligand resulting from loss of Te and monoprotonation were obtained. In reactions with RPCl₂ (R = ^tBu, Ad, ⁱPr₂N) a significant difference was observed between Se- and S-containing systems. In the former case, Se,Se′-chelated derivatives were formed in high yields, whereas the N,S-chelated isomers predominated for sulfur. All complexes were characterized by multinuclear (¹H, ³¹P, ⁷⁷Se, ¹¹⁹Sn, and ¹²⁵Te) NMR spectroscopy; this technique was especially useful in the analysis of the mixture of (<b>L</b>)­(Se) and (<b>L</b>)­(SeSe) obtained from the reaction of Se₂Cl₂ with <b>L</b>^2– (E = Te). Single-crystal X-ray structures were obtained for the spirocyclic In complex (<b>9</b>), (<b>L)</b>GePh₂ (E = Te, <b>10</b>), (<b>L)</b>Sn^tBu₂ (E = Te, <b>12a</b>); E = Se, <b>12aSe</b>, E = S, <b>12aS</b>) and (<b>L</b>)­(μ-SeSe) (E = Te, <b>16</b>)

Synthetic, structural, and spectroscopic studies of sterically crowded tin-chalcogen acenaphthenes

The work in this project was supported by the Engineering and Physical Sciences Research Council (EPSRC) and EaStCHEM.A series of sterically encumbered peri-substituted acenaphthenes have been prepared containing chalcogen and tin moieties at the close 5,6-positions (Acenap[SnPh3][ER], Acenap = acenaphthene-5,6-diyl, ER = SPh (1), SePh (2), TePh (3), SEt (4); Acenap[SnPh2Cl][EPh], E = S (5), Se (6); Acenap[SnBu2Cl][ER], ER = SPh(7), SePh (8), SEt (9)). Two geminally bis(peri-substituted) derivatives ({Acenap[SPh2]}2SnX2, X = Cl (10), Ph (11)) have also been prepared, along with the bromo–sulfur derivative Acenap(Br)(SEt) (15). All 11 chalcogen–tin compounds align a Sn–CPh/Sn–Cl bond along the mean acenaphthene plane and position a chalcogen lone pair in close proximity to the electropositive tin center, promoting the formation of a weakly attractive intramolecular donor–acceptor E···Sn–CPh/E···Sn–Cl 3c-4e type interaction. The extent of E→Sn bonding was investigated by X-ray crystallography and solution-state NMR and was found to be more prevalent in triorganotin chlorides 5–9 in comparison with triphenyltin derivatives 1–4. The increased Lewis acidity of the tin center resulting from coordination of a highly electronegative chlorine atom was found to greatly enhance the lp(E)−σ*(Sn–Y) donor–acceptor 3c-4e type interaction, with substantially shorter E–Sn peri distances observed in the solid state for triorganotin chlorides 5–9 (∼75% ∑rvdW) and significant 1J(119Sn,77Se) spin–spin coupling constants (SSCCs) observed for 6 (163 Hz) and 8 (143 Hz) in comparison to that for the triphenyltin derivative 2 (68 Hz). Similar observations were observed for geminally bis(peri-substituted) derivatives 10 and 11.PostprintPeer reviewe

Main Group Tellurium Heterocycles Anchored by a P₂^VN₂ Scaffold and Their Sulfur/Selenium Analogues

A comprehensive investigation of reactions of alkali-metal derivatives of the ditelluro dianion [TeP^V(N^tBu)­(μ-N^tBu)]₂^2– (<b>L</b>^2–, E = Te) with p-block element halides produced a series of novel heterocycles incorporating P₂^VN₂ rings, tellurium, and group 13–16 elements. The dianion engages in Te,Te′-chelation to the metal center in Ph₂Ge and R₂Sn (R = ^tBu, ⁿBu, Ph) derivatives; similar behavior was noted for group 14 derivatives of <b>L</b>^2– (E = S, Se). In the case of group 13 trihalides MCl₃ (M = Ga, In), neutral spirocyclic complexes (<b>L</b>)­M­[N^tBu­(Te)­P^V(μ-N^tBu)₂P^IIIN­(H)^tBu)] (M = Ga, In) comprised of a Te,Te′-chelated ligand <b>L</b>^2– and a N,Te-bonded ligand resulting from loss of Te and monoprotonation were obtained. In reactions with RPCl₂ (R = ^tBu, Ad, ⁱPr₂N) a significant difference was observed between Se- and S-containing systems. In the former case, Se,Se′-chelated derivatives were formed in high yields, whereas the N,S-chelated isomers predominated for sulfur. All complexes were characterized by multinuclear (¹H, ³¹P, ⁷⁷Se, ¹¹⁹Sn, and ¹²⁵Te) NMR spectroscopy; this technique was especially useful in the analysis of the mixture of (<b>L</b>)­(Se) and (<b>L</b>)­(SeSe) obtained from the reaction of Se₂Cl₂ with <b>L</b>^2– (E = Te). Single-crystal X-ray structures were obtained for the spirocyclic In complex (<b>9</b>), (<b>L)</b>GePh₂ (E = Te, <b>10</b>), (<b>L)</b>Sn^tBu₂ (E = Te, <b>12a</b>); E = Se, <b>12aSe</b>, E = S, <b>12aS</b>) and (<b>L</b>)­(μ-SeSe) (E = Te, <b>16</b>)

Geometrically enforced donor-facilitated dehydrocoupling leading to an isolable arsanylidine-phosphorane

This work was made open access through funds from the RCUK open access block grant.A proximate Lewis basic group facilitates the mild dehydrogenative P–As intramolecular coupling in the phosphine-arsine peri-substituted acenaphthene 3 , affording thermally and hydrolytically stable arsanylidine-phosphorane 4 with a sterically accessible two-coordinate arsenic atom. The formation of 4 is thermoneutral due to the dehydrogenation being concerted with the donor coordination. Reaction of 4 with a limited amount of oxygen reveals arsinidene-like reactivity via formation of cyclooligoarsines, supporting the formulation of the bonding in 4 as base-stabilized arsinidene R3P→AsR.Publisher PDFPeer reviewe