A versatile synthesis, including asymmetric synthesis, of bicyclo[n.1.0]alkanes from cyclic ketones via the magnesium carbenoid 1,3-CH insertion as a key reaction

Treatment of 1-chlorovinyl p-tolyl sulfoxides, which were synthesized from various cyclic ketones and chloromethyl p-tolyl sulfoxide in three steps, in high yields, with lithium enolate of tert-butyl acetate or its homologues gave the adducts in quantitative yields. The adducts were treated with isopropylmagnesium chloride in ether in dry toluene as the reaction solvent to afford bicyclo[n.1.0]alkanes in high to quantitative yields via magnesium carbenoid 1,3-CH insertion. When this method was carried out starting from unsymmetrical cyclic ketones and (R)-chloromethyl p-tolyl sulfoxide, an asymmetric synthesis of bicyclo[n.1.0]alkane was realized.     

类水滑石及其杂多阴离子柱撑物的合成与表面酸性研究

合成了一些类水滑石和过渡金属取代型杂多酸盐，并由此制备了相应杂多阴离子柱撑水滑石层柱材料。用ＸＲＤ，ＩＲ和元素分析等手段对合成产物进行组成和结构表征，用ＮＨ３－ＴＰＤ，Ｐｙ－ＩＲ研究了合成产物的表面酸性和酸类型，并在异丙醇反应中考察了合成物的酸碱催化行为，结果表明，水滑石和柱撑水滑石均同时存在酸碱中心，且酸碱相对强度与柱阴离子类型密切相关。杂多阴离子进入水滑石层，同时改变了水滑石和杂多酸盐的酸强度     

A new approach for the construction of a highly congested bicyclic system in polycyclic polyprenylated acylphloroglucinols (PPAPs)

A highly congested bicyclo[3.3.1]nonanone core of polycyclic polyprenylated acylphloroglucinols was constructed using a stereoselective Claisen rearrangement and an intramolecular aldol reaction as the key steps. The stereochemistry of C-4 appeared to control the ground state conformation of the cyclohexenone core, which determined the diastereoselectivity in the Claisen rearrangement.     

Synthese und Geruch von (E)- und (Z)-bis-homo-ß-Santalol

Summary The synthesis of the title compounds is described. Guided by theoretical considerations and molecular modeling studies, the influence of the bulky group opposite to the osmophorically important primary hydroxyl function on the odour impression is determined. The organoleptic evaluation proved the predicted sandal like odour of the (Z)-isomer and its also predicted absence with (E)-isomer. A moderate increase of the volume of the bulky group shows no influence on the sandalwood odour of the new analogue.

     

Rare Earth-Rich Indides <Emphasis Type="Italic">RE</Emphasis><Subscript>5</Subscript>Pt<Subscript>2</Subscript>In<Subscript>4</Subscript> (<Emphasis Type="Italic">RE</Emphasis> = Sc,Y, La–Nd,Sm, Gd–Tm,Lu)

Summary. The isotypic indides RE ₅Pt₂In₄ (RE = Sc, Y, La–Nd, Sm, Gd–Tm, Lu) were synthesized by arc-melting of the elements and subsequent annealing. They were investigated via X-ray powder diffraction. Small single crystals of Gd₅Pt₂In₄ were grown via slow cooling and the structure was refined from X-ray single crystal diffractometer data: Pbam, a = 1819.2(9), b = 803.2(3), c = 367.6(2) pm, wR ² = 0.089, 893 F ² values and 36 parameters. The structure is an intergrowth variant of distorted trigonal and square prismatic slabs of compositions GdPt and GdIn. Together the platinum and indium atoms build up one-dimensional [Pt₂In₄] networks (292–333 pm Pt–In and 328–368 pm In–In) in an AA stacking sequence along the c axis. The gadolinium atoms fill distorted square and pentagonal prismatic cages between these networks with strong bonding to the platinum atoms.     

meta-Photoaddition reactions of 2-chloro-, 2,5-dichloro-, and 2-halo-5-isopropyl-tropones with 9,10-dicyanoanthracene

Photoreactions of 2-halotropones with the excited 9,10-dicyanoanthracene gave a meta-adduct and substitution products occurred at the C-2 position of troponoids. The mechanism of the meta-adduct was proved by the product analysis of the reaction of 3,7-dideuterio-2-bromo-5-isopropyltropone and 9,10-dicyanoanthracene. In the photoreaction of 2-chloro-5-isopropyltropone and 9,10-dicyanoanthracene in a mixed solvent of benzene and methanol, a benzaldehyde with a dibenzo-2-oxabicyclo[3.2.2]nonane system was obtained to support occurrence of an [8+4] cycloaddition reaction between them.     

活性氮与SO2和SOCl2的传能反应

在流动余辉装置上, 研究了活性氮与SO2和SOCl2之间的反应过程. 在280～500 nm, 观察到了SO2( A1A2,B1B1→X1A1 )和SO2(a3B1→X1A1)的发射光谱. 对比由Ar(3P0,2)与N2碰撞反应产生的纯N2(A3Σu+)与SO2、SOCl2之间反应的实验结果, 可以说明, N2(A3Σu+)在活性氮与SO2的反应中是主要的能量载体, 它与SO2的直接能量转移反应形成了激发态的SO2(A1A2, B1B1); 在活性氮与SOCl2的反应中观测到的激发态SO2(a3B1), 则可能主要是通过N(4S)与SOCl2反应生成的N2O(X1Σ+)和N2(A3Σu+)与SOCl2反应生成的SO(X3Σ－)之间的化学反应过程产生.     

芳香化合物STM研究的进展

本文系统介绍了用STM技术研究苯、萘和蒽等芳香化合物的诸多成果，表明分子间相互作用、分子与基底间相互作用等对该类化合物吸附结构的影响，以及溶液中分子的结构、结构转化及表面反应与电极电位的关系，阐明了在原子分子惊讶上研究芳香化合物的重要性及发展趋势。     

Ionic Ozonides

Ionic Ozonides [1] were mentioned for the first time during the second half of the nineteenth century. However, fundamental aspects of their chemistry and physics remained obscure until more recently procedures had been provided that allow for their syntheses in gram‐amounts, and in high purity. Respective preparative approaches start by reacting the alkali metal superoxides KO₂, RbO₂, or CsO₂ with O₂/O₃ mixtures, at punctilious temperature control. Subsequently, the raw product is extracted with liquid ammonia. From the solution obtained, solid ozonides are harvested and purified by recrystallization. As rather versatile and efficient accesses to ozonides of further cations, metathesis reactions or cation exchange in liquid ammonia have been developed. The samples obtained have allowed for full structural and basic physical characterizations. All ionic ozonides known are metastable with respect to release of dioxygen, [NMe₄]O₃ being the most stable one (onset of rapid decomposition at 348 K). Depending on the respective crystal field, the bond lengths and angles of the ozonide anion vary significantly, and consistently, from 135 to 129 pm, and 113 to 120°, respectively. The magnetic moments of the paramagnetic O₃^? determined by susceptibility measurements (1.70–1.80 μ_B) deviate but slightly from the spin‐only value for one unpaired electron. This finding complies well with the small anisotropy of the g‐factors. As an achievement of possibly far reaching consequences, stable solutions of ionic ozonides in organic solvents have become available, opening the way to the use of O₃^? as a ligand, or synthon, in coordination and molecular chemistry.     

Zur Synthese von Homocamphenilansäure

Syntheses of the title compound and of some of its derivatives are described. Homocamphenilanic acid could not be obtained by aDiels-Alder reaction of cyclohexadiene with an appropriate dienophile but is easily accessible via homocamphene by hydroboration of this homoterpene and subsequent oxidation of the reaction product.

Anmerkung: Zur Verwendung der Vorsilbe Homo- im Zusammenhang mit Norbornanen siehe Lit. [13] und Fußnote in Lit. [12].