We use data from the General Social Survey (GSS) over a 40-year period (1973-2012) to evaluate changes in attitudes about pornography and pornography consumption among American young adults. One of the major challenges in making comparisons across birth generations is separating the effect of birth cohort from age and period effects. We use an intrinsic estimator to separately identify the effects of age, birth cohort, and time period using 40 years of repeated cross-section data. We find that, relative to the general population, young people's beliefs about whether pornography should be illegal have stayed relatively constant over this 40-year period and, if anything, have slightly increased. We also find that pornography consumption has been increasing across birth generations, though this increase has been smaller than would be inferred based on differences across generations at a single point in time, due to a strong age component in consumption patterns.

The alkaline-earth elements (Be, Mg, Ca, Sr, and Ba) strongly favor the formation of diamagnetic compounds in the +2 oxidation state. Herein we report a paramagnetic beryllium radical cation, [(CAAC) 2 Be] +• (2) [CAAC = cyclic (alkyl)(amino)carbene], prepared by oxidation of a zero-valent beryllium complex with 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO). Compound 2 was characterized by EPR spectroscopy, elemental analysis, X-ray crystallography, and DFT calculations. Notably, the isolation of 2 represents the first s-block charged radical and the first crystalline beryllium radical.

We report a combined experimental and theoretical study on the first examples of carbodicarbene (CDC)‐stabilized bismuth complexes, which feature low‐coordinate cationic bismuth centers with C=Bi multiple‐bond character. Monocations [(CDC)Bi(Ph)Cl][SbF6] (8) and [(CDC)BiBr2(THF)2][SbF6] (11), dications [(CDC)Bi(Ph)][SbF6]2 (9) and [(CDC)BiBr(THF)3][NTf2]2 (12), and trication [(CDC)2Bi][NTf2]3 (13) have been synthesized via sequential halide abstractions from (CDC)Bi(Ph)Cl2 (7) and (CDC)BiBr3 (10). Notably, the dications and trication exhibit C⇉ Bi double dative bonds and thus represent unprecedented bismaalkene cations. The synthesis of these species highlights a unique non‐reductive route to C−Bi π‐bonding character. The CDC‐[Bi] complexes (7–13) were compared with related NHC‐[Bi] complexes (1, 3–6) and show substantially different structural properties. Indeed, the CDC ligand has a remarkable influence on the overall stability of the resulting low‐coordinate Bi complexes, suggesting that CDC is a superior ligand to NHC in heavy pnictogen chemistry.

The first examples of carbodicarbene (CDC)-s-block complexes have been synthesized. Unusual C–H bond activation and cyclization discovered.

No abstract

In the past two decades, the organometallic chemistry of the alkaline earth elements has experienced a renaissance due in part to developments in ligand stabilization strategies. In order to expand the scope of redox chemistry known for magnesium and beryllium, we have synthesized a set of reduced magnesium and beryllium complexes and compared their resulting structural and electronic properties. The carbene-coordinated alkaline earth−halides, ( Et2 CAAC)-MgBr 2 (1), (SIPr)MgBr 2 (2), ( Et2 CAAC)BeCl 2 (3), and (SIPr)BeCl 2 (4) [ Et2 CAAC = diethyl cyclic(alkyl)(amino) carbene; SIPr = 1,3-bis(2,6-diisopropylphenyl)-4,5-dihydroimidazole-2-ylidene] were combined with an α-diimine [2,2bipyridine (bpy) or bis(2,6-diisopropylphenyl)-1,4-diazabutadiene ( Dipp DAB)] and the appropriate stoichiometric amount of potassium graphite to form singly-and doubly-reduced compounds ( Et2 CAAC)MgBr( Dipp DAB) (5), ( Et2 CAAC)MgBr(bpy) ( 6), ( Et2 CAAC)Mg( Dipp DAB) ( 7), ( Et2 CAAC)Be(bpy) (8), and (SIPr)Be(bpy) (9). The doubly-reduced compounds 7−9 exhibit substantial π-bonding interactions across the diimine core, metal center, and π-acidic carbene. Each complex was fully characterized by UV−vis, FT-IR, X-ray crystallography, 1 H, 13 C, and 9 Be NMR, or EPR where applicable. We use these compounds to highlight the differences in the organometallic chemistry of the lightest alkaline earth metals, magnesium and beryllium, in an otherwise identical chemical environment.

A common feature of d‐ and p‐block elements is that they participate in multiple bonding. In contrast, the synthesis of compounds containing homo‐ or hetero‐nuclear multiple bonds involving s‐block elements is extremely rare. Herein, we report the synthesis, molecular structure, and computational analysis of a beryllium imido (Be=N) complex (2), which was prepared via oxidation of a molecular Be0 precursor (1) with trimethylsilyl azide Me3SiN3 (TMS‐N3). Notably, compound 2 features the shortest known Be=N bond (1.464 Å) to date. This represents the first compound with an s‐block metal‐nitrogen multiple bond. All compounds were characterized experimentally with multi‐nuclear NMR spectroscopy (1H, 13C, 9Be) and single‐crystal X‐ray diffraction studies. The bonding situation was analyzed with density functional theory (DFT) calculations, which supports the existence of π‐bonding between beryllium and nitrogen.

The synthesis and thermal redox chemistry of the first antimony (Sb)– and bismuth (Bi)–phosphaketene adducts are described. When diphenylpnictogen chloride [Ph 2 PnCl (Pn = Sb or Bi)] is reacted with sodium 2-phosphaethynolate [Na[OCP]·(dioxane) x ], tetraphenyldipnictogen (Ph 2 Pn–PnPh 2 ) compounds are produced, and an insoluble precipitate forms from solution. In contrast, when the N -heterocyclic carbene adduct (NHC)–PnPh 2 Cl is combined with [Na[OCP]·(dioxane) x ], Sb– and Bi–phosphaketene complexes are isolated. Thus, NHC serves as an essential mediator for the reaction. Immediately after the formation of an intermediary pnictogen–phosphaketene NHC adduct [NHC–PnPh 2 (PCO)], the NHC ligand transfers from the Pn center to the phosphaketene carbon atom, forming NHC–C(O)P-PnPh 2 [Pn = Sb ( 3 ) or Bi ( 4 )]. In the solid state, 3 and 4 are dimeric with short intermolecular Pn–Pn interactions. When compounds 3 and 4 are heated in THF at 90 and 70 °C, respectively, the pnictogen center Pn III is thermally reduced to Pn II to form tetraphenyldipnictines (Ph 2 Pn–PnPh 2 ) and an unusual bis -carbene-supported OCP salt, [(NHC) 2 OCP][OCP] ( 5 ). The formation of compound 5 and Ph 2 Pn–PnPh 2 from 3 or 4 is unique in comparison to the known thermal reactivity for group 14 carbene–phosphaketene complexes, further highlighting the diverse reactivity of [OCP] − with main-group elements. All new compounds have been fully characterized by single-crystal X-ray diffraction, multinuclear NMR spectroscopy ( 1 H, 13 C, and 31 P), infrared spectroscopy, and elemental analysis ( 1 , 2 , and 5 ). The electronic structure of 5 and the mechanism of formation were investigated using density functional theory (DFT).