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The reaction of 8-dimethylaminonaphthyllithium etheratewith thetellurium(II) bis(dithiocarbamate) Te(S2CNEt2)2provided the diaryltelluride (8-Me2NC10H6)2Te (1). The oxidationof 1with an excess of H2O2didnot afford the expected diaryltellurium(IV) oxide (8-Me2NC10H6)2TeO (2), butthe diaryltellurium(VI) dioxide (8-Me2NC10H6)2TeO2(3). The preparationof 2was achieved by the comproportionation reactionof 1and 3. The protonation of 2using triflic acid gave rise to the formation of diarylhydroxytelluroniumtriflate [(8-Me2NC10H6)2Te(OH)](O3SCF3) (4), which featuresthe protonated diaryltellurium oxide [(8-Me2NC10H6)2Te(OH)](4a).Compounds 1, 3·H2O·H2O2, 3·2H2O, and 4were characterized by X-ray crystallography. The experimentallyobtained molecular structures were compared to those calculated for 1–3, 4a, and (8-Me2NC10H6)2Te(OH)2(5) as well as the related diphenyltellurium compounds Ph2Te (6), Ph2TeO (7), Ph2TeO2(8), [Ph2Te(OH)](9a), and Ph2Te(OH)2(10) at the DFT/B3PW91 level of theory. [ABSTRACT FROM AUTHOR]

The oxidation of the telluroxane cluster (8-Me2NC10H6Te)6O8(OH)2(4) or the diaryl ditelluride (8-Me2NC10H6Te)2(7) usingH2O2provided the diarylditelluronic acid [8-Me2NC10H6Te(O)(OH)2]2(O) (6), which is the second member of this compoundclass and the first one to contain an intramolecularly coordinatedsubstituent. Attempts at recrystallizing 6from Methanolprovided the partial ester [8-Me2NC10H6Te(O)(OH)(OMe)]2(O) (8). In addition structuralmotifs of known diaryltelluronic acids were compared using DFT calculations. [ABSTRACT FROM AUTHOR]

Depending on the reaction conditions, the base hydrolysis of (2,6-Mes2C6H3In)2(μ-Cl)2Cl2(1) in a two-layer system of aqueous NaOH/diethyl ether or toluene afforded 2,6-Mes2C6H3InCl2·H2O (2), (2,6-Mes2C6H3In)2(μ-OH)2Cl2(3), (2,6-Mes2C6H3In)3(μ-OH)4Cl2(4), and (2,6-Mes2C6H3In)4(μ-OH)8(5), respectively, in high yields. The indoxane 5can be regarded as a heavier and aggregated congener of arylboronic acids. An attempt at preparing (2,6-Mes2C6H3Tl)2(μ-Cl)2Cl2(6) by the chlorination of 2,6-Mes2C6H3Tl (prepared in situ from 2,6-Mes2C6H3Li and TlCl) using SO2Cl2provided the isomeric diarylthallium cation [(2,6-Mes2C6H3)2Tl]TlCl4(7). The exposure of crude reaction mixture consisting of 2,6-Mes2C6H3Tl and LiCl to moist air surprisingly produced (2,6-Mes2C6H3Tl)2(μ-OH)2Cl2(8), which reacted with hydrochloric acid to give 6. Base hydrolysis of 8in a two-layer system of aqueous NaOH/CHCl3proceeded with partial cleavage of the m-terphenyl substituents and yielded the thalloxane cluster (2,6-Mes2C6H3Tl)4Tl2(μ3-O)4(μ-OH)6(9) in moderate yield. Compounds 1−9were characterized by X-ray crystallography. [ABSTRACT FROM AUTHOR]

The syntheses are reported of the molecular arylantimony oxo compounds [(2,6-Mes2C6H3Sb)2(O)(OH)4SO4] (1) and [Na2(2,6-Mes2C6H3Sb)4O4(OH)10·2H2O] (2), which were obtained by the reaction of the dinuclear stibonic acid [2,6-Mes2C6H3Sb(O)(OH)]2with aqueous H2SO4and NaOH, respectively. The molecular structures of 1and 2were established by X-ray crystallography. [ABSTRACT FROM AUTHOR]

Benzene-1,3,5-tri- p-phenylphosphonic acid, 1,3,5-[ p-C 6H 4P(O)(OH) 2] 3C 6H 3, ( 8), a novel building block for applications in supramolecular chemistry, was prepared in two steps with an overall yield of 82%. The [Pd(PPh 3) 4]-catalyzed Arbuzov reaction of 1,3,5-tris( p-bromophenyl)benzene with P(O i-Pr) 3afforded benzene-1,3,5-tri- p-phenylphosphonic diisopropyl ester, 1,3,5-[ p-C 6H 4P(O)(O i-Pr) 2] 3C 6H 3( 9). The hydrochloric acid-catalyzed hydrolysis of 9produced 8, which forms a crystalline salt with p-dimethylaminopyridine (DMAP) in a ratio of 2:3 (as methanol solvate) that was characterized by X-ray crystallography. The supramolecular structure features organic domains of stapled 1,3,5-triphenylbenzene units associated by PO−H···OP hydrogen bonds and π-stacking. These staples are horizontally cross-linked by PO−H···OP hydrogen bonds. The protonated DMAP molecules fill the voids between the staples and participate in the stabilization of the framework by formation of N−H···OP hydrogen bonds. The melting point of the adduct (381 °C) confirms the high thermal stability of the supramolecular framework. [ABSTRACT FROM AUTHOR]

series of enantiomerically pure bis(myrtanyl)tin compounds, cis-Myr 2SnX 2( 1, X = Ph; 3, X = Cl; 5, X = H) and trans-Myr 2SnX 2( 2, X = Ph; 4, X = Cl; 6, X = H) were prepared starting from (–)-1S-β-pinene and characterized by multinuclear NMR spectroscopy and in case of 3and 4also by X-ray crystallography. The reduction of 3and 4with Mg selectively produced pentastannane rings, cyclo-( cis-Myr 2Sn) 5( 7) and cyclo-( trans-Myr 2Sn) 5( 8), while the dehydropolymerization of 5and 6produced a mixture of polystannanes, poly( cis-Myr 2Sn) n( 9) or poly( trans-Myr 2Sn) n( 10), and oligomers that could not be separated. The pentastannane rings gave rise to UV absorptions at λ max219 and 217 nm, which were assigned to σ → σ* transitions of the Sn−Sn bonds. Due to the increased σ-electron delocalization, the polystannanes 9and 10show red-shifted UV absorptions at λ max416 and 417 nm. The CD spectra of the polystannanes 9and 10reveal a positive cotton effect at λ max422 and 425 nm, consistent with the idea that the chiral information is transferred from the UV-inactive myrtanyl groups to the polymer backbone, which most likely adopts a helical conformation with the right-handed screw sense being in excess. [ABSTRACT FROM AUTHOR]

Hydrogen bonding of the type SiO−H···A (A O, N) has been studied in the gas phase for simple H3SiOH·acceptor complexes with the acceptor molecules being O(H)SiH3, OH2, O(H)CH3, O(CH3)2, O(CH3)SiH3, O(SiH3)2, NH3, N(CH3)H2, N(CH3)2H, N(CH3)3, N(CH3)2C6H5, and NC5H5, respectively, at the B3LYP/6-311(2d,p) level of theory, using Bader''s atoms in molecules (AIM) and Weinhold''s natural bond orbital (NBO) methodology. For all complexes (except H3SiOH·N(CH3)2C6H5) the complex energy Eadd.is a good estimate for the hydrogen bond energy EHB, which is generally higher in N-acceptor complexes (−5.52 to −7.17 kcal mol-1) than in O-acceptor complexes (−2.09 to −5.06 kcal mol-1). In case of H3SiOH·N(CH3)2C6H5, EHBand Eadd.differ by the energy associated with the loss of n(N)→ conjugation in N(CH3)2C6H5upon complex formation. EHBshows no correlation with O···A distances and the red shifts (OH) of the OH-stretching vibrations when different acceptors are compared, although both parameters are commonly used to estimate the strength of the hydrogen bond from spectroscopic and diffraction data. A good linear correlation of the hydrogen bond energy EHBhas been established with parameters derived from the AIM and NBO analyses, namely, the electron densities (HA) and (OH) at the H···A and O−H bond critical points (BCPs) and the NLMO bond orders BONLMO(HA) of the H···A bonds of the H3SiOH·acceptor complexes as well as the change of natural charges qNPA(O) at the O-donor atom upon H3SiOH·acceptor complex formation. Hydrogen bonding of the type SiO−H···A (A O, N) has been also studied in the related cyclic multiple H3SiOH·acceptor complexes (H3SiOH)3, (H3SiOH)2·NC5H5, and (H3SiOH)4, respectively, at the same level of theory. Cooperative hydrogen bonding is evident for all cyclic multiple H3SiOH·acceptor complexes, whereby the strongest concomitant strengthening of the hydrogen bonds is observed for (H3SiOH)4and (H3SiOH)2·NC5H5. [ABSTRACT FROM AUTHOR]

The reaction of 8-dimethylamino-1-naphthyllithium diethyl etherate with tellurium powder and subsequent O2oxidation was reinvestigated. Besides the previously reported bis[8-(dimethylamino)naphthyl] ditelluride (1), the new bis[8-(dimethylamino)naphthyl] tritelluride (2) was isolated in 42% yield and fully characterized. Low-temperature 125Te NMR spectroscopy provides evidence to suggest that analytically pure 2is in equilibrium with 1and bis[8-(dimethylamino)naphthyl] tetratelluride (2a). [ABSTRACT FROM AUTHOR]

The kinetically controlled base hydrolysis of the sterically encumbered arylantimony dichloride 2,6-Mes2C6H3SbCl2(1) under aerobic conditions afforded 2,6-Mes2C6H3(Cl)SbIII2O (2) and the mixed-valent clusters (2,6-Mes2C6H3SbV)2(ClSbIII)4O8(3) and (2,6-Mes2C6H3SbV)4(ClSbIII)4(HOSbIII)2O14(4), whose molecular structures are dominated by hypervalent and secondary bonding. [ABSTRACT FROM AUTHOR]

Condensation of t-Bu2Si(OH)2with (p-MeOC6H4)2TeO in a Si/Te ratio of 1:1.2 exclusively produced the 12-membered tellurasiloxane ring cyclo-(p-MeOC6H4)2TeOSit-Bu2O3(1), whose molecular structure was determined by X-ray crystallography. At larger Si/Te ratios, the open-chain tellurasiloxanes HOt-Bu2SiOR2TeOSit-Bu2OH (2, R p-MeOC6H4) and HOt-Bu2SiOR2TeOSit-Bu2OR2TeOSit-Bu2OH (3, R p-MeOC6H4) were identified in solution by 29Si and 125Te NMR spectroscopy along with 1and unreacted t-Bu2Si(OH)2. The analogous reaction of Ph2Si(OH)2with (p-MeOC6H4)2TeO did not provide tellurasiloxanes, but led to the formation of the known siloxanes rings cyclo-(Ph2SiO)3and cyclo-(Ph2SiO)4. [ABSTRACT FROM AUTHOR]

The solid-state structure of a potassium methylstannoxyl carbonate cluster, K6[MeSn(O)CO3]6·14H2O (2), a significant intermediate in the synthesis of methylstannonic acid [MeSn(O)OH]n(1), was investigated by X-ray crystallography. The hexameric methylstannoxyl carbonate ion [MeSn(O)CO3]66−features the common drum-type structure observed for many neutral organostannoxyl carboxylates [RSn(O)CO2R′]6(R, R′ = alkyl, aryl). Compounds 1and 2were also studied by 119Sn MAS NMR spectroscopy. [ABSTRACT FROM AUTHOR]