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Improved Method for the Synthesis of Alkyl Azides¹

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTImproved Method for the Synthesis of Alkyl Azides1EUGENE LIEBER, TAI SIANG CHAO, and C. N. RAMACHANDRA RAOCite this: J. Org. Chem. 1957, 22, 3, 238–240Publication Date (Print):March 1, 1957Publication History Published online1 May 2002Published inissue 1 March 1957https://pubs.acs.org/doi/10.1021/jo01354a003https://doi.org/10.1021/jo01354a003research-articleACS PublicationsRequest reuse permissionsArticle Views1073Altmetric-Citations41LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

Organically Templated Mixed-Valent Iron Sulfates Possessing Kagome and Other Types of Layered Networks

No abstract is provided for this article.

Novel experiments with carbon nanotubes: opening, filling, closing and functionalizing nanotubes

No abstract is provided for this article.

New Solvothermal Routes for GaN Nanocrystals

GaN nanocrystals (see Figure) of hexagonal structure and varying diameters have been prepared by the reaction of hexamethyldisilazane (HMDS) with gallium cupferron or GaCl 3 under solvothermal conditions. The nanocrystals show a size‐dependent photoluminescence band in the 260–320 nm region, characteristic of quantum confinement.

Nanocrystalline Films of Au−Ag, Au−Cu, and Au−Ag−Cu Alloys Formed at the Organic−Aqueous Interface

By the reaction of the appropriate organometallic precursors and tetrakishydroxymethyl phosphonium chloride (THPC) at the toluene-water interface, we have prepared nanocrystalline films of Au-Ag and Au-Cu alloys with a range of compositions. The films have been characterized by X-ray diffraction, electron microscopy, optical spectroscopy, and other techniques, besides compositional analysis. The particle size of the nanocrystals in the films varies with the composition. The surface plasmon band of the alloy films as well as of the organosols obtained by the disintegration of the films by the addition of an alkanethiol show the expected composition dependence. It has been possible to prepare the nanocrystalline films of a ternary Au-Ag-Cu alloy.

Nanostructured Peptide Fibrils Formed at the Organic−Aqueous Interface and Their Use as Templates To Prepare Inorganic Nanostructures

Formation of fibril-type nanostructures of the Alzheimer's β-amyloid diphenylalanine (l-Phe-l-Phe, FF) at the organic−aqueous interface and the factors affecting their structures have been investigated. Such nanostructures are also formed by bovine serum albumin and bovine pancreas insulin. The concentration of the precursor taken in the aqueous layer plays an important role in determining the morphology of the nanostructures. The addition of curcumin to the organic layer changes the structure of the self-assembled one-dimensional aggregates of diphenylalanine. By coating the diphenylalanine dipeptide fibrils with appropriate precursors followed by calcination in air, it has been possible to obtain one-dimensional nanostructures of inorganic materials.

Electronic structures and reactivities of monometallic and bimetallic clusters of Au and Cu

No abstract is provided for this article.

ChemInform Abstract: Porous Materials: a Case Study of Supramolecular Organization in Materials Design

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform Abstract: An Open‐Framework Iron Phosphate with Large Voids, Exhibiting Spin‐Crossover.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Enhancement of ferromagnetism by Co and Ni substitution in the perovskite LaBiMn2O6+δ

The substitution of cobalt and nickel for manganese in the perovskite manganate LaBiMn2O6+δ has been realized, leading to the perovskites LaBiMn2−MxO6+δ, with M = Co, Ni and 0 ≤ x ≤ 2/3. In contrast to the literature these phases are found to be orthorhombic with Pnma symmetry. More importantly, it is shown that ferromagnetism is enhanced, TC being increased from 80 K for the parent compound (x = 0) to 97 K for the Ni phase, and to 130 K for the Co phase. Moreover, strong competition between ferromagnetism and a glassy-ferromagnetic state in the case of nickel or spin-glass behaviour in the case of cobalt is observed. These phenomena are interpreted in the frame of a phase separation scenario, where the ferromagnetic Mn4+/Ni2+ and Mn4+/Co2+ interactions reinforce the Mn3+/Mn4+ interactions. These compounds are found to be insulating with a relatively large positive value of thermoelectric power.

Structure-property relations

Relating properties of substances to their structures has been a major objective of modern chemistry and this also happens to be a prime concern of solid state chemists. Some of the aspects of importance in solid state chemistry are electronic, magnetic, superconducting, dielectric and optical properties. We shall briefly discuss these properties and present highlights in the solid state chemistry of some interesting classes of materials. An important class of materials is that of ferroics, which possess several orientation states that can be switched from one to another by the application of an appropriate force; ferroelectric materials form a subgroup of this class of materials. Other classes of materials discussed are amorphous solids, mixed-valence compounds, low-dimensional solids and liquid crystals which are of considerable importance. We have also devoted attention to different types of metal-nonmetal transitions and have briefly examined the question, ‘what makes a metal?’. While a detailed discussion of the theory of electronic structure would be outside the scope of the book, we have presented the necessary background material at an elementary level and discussed some of the typical results obtained from empirical theory as well as electron spectroscopy.

Remarkable Improvement in the Mechanical Properties and CO₂ Uptake of MOFs Brought About by Covalent Linking to Graphene

Metal-organic frameworks (MOFs) are exceptional as gas adsorbents but their mechanical properties are poor. We present a successful strategy to improve the mechanical properties along with gas adsorption characteristics, wherein graphene (Gr) is covalently bonded with M/DOBDC (M=Mg(2+) , Ni(2+) , or Co(2+) , DOBDC=2,5-dioxido-1,4-benzene dicarboxylate) MOFs. The surface area of the graphene-MOF composites increases up to 200-300 m(2) g(-1) whereas the CO2 uptake increases by ca. 3-5 wt % at 0.15 atm and by 6-10 wt % at 1 atm. What is significant is that the composites exhibit improved mechanical properties. In the case of Mg/DOBDC, a three-fold increase in both the elastic modulus and hardness with 5 wt % graphene reinforcement is observed. Improvement in both the mechanical properties and gas adsorption characteristics of porous MOFs on linking them to graphene is a novel observation and suggests a new avenue for the design and synthesis of porous materials.

Fullerenes, nanotubes, onions and related carbon structures

Fullerenes, containing five- and six-membered carbon rings, of which C60 and C70 are the prominent members, exhibit phase transitions associated with orientational ordering. When C60 is suitably doped with electrons, it shows novel superconducting and magnetic properties. We review these and other properties of fullerenes in bulk or in film form along with the preparative and structural aspects. Carbon nanotubes and onions (hyperfullerenes) are the other forms of carbon whose material properties have aroused considerable interest. Besides discussing these new forms of carbon, we briefly introduce other possible forms, such as those involving five-, six- and seven-membered rings and hybrids between diamond and graphite.

Automated Building Damage Classification using Deep Learning for Efficient Disaster Response and Recovery

Recent theoretical studies of the hydrogen bond

No abstract is provided for this article.

ChemInform Abstract: Inorganic Analogues of Graphene

Review: MoS 2 , WS 2 , BN or BCN; 50 refs.

Covalent Functionalization of Nanosheets of MoS₂ and MoSe₂ by Substituted Benzenes and Other Organic Molecules

Covalent functionalization has been effectively employed to attach benzene functionalities to MoS2 and MoSe2 nanosheets by the reaction with para-substituted iodobenzenes bearing -OCH3 , -H, and -NO2 as the substituents, where the electron-donating and electron-withdrawing power of the para substituent varies significantly. The functionalization is based on the formation of a C-S or C-Se linkage at the expense of the C-I bond on reaction of the iodobenzene with electron-rich 1T-MoS2 or 1T-MoSe2 . The degree of functionalization is in the range 4-24 % range, the value increases with the electron-withdrawing power of the para substituent. Semiconducting 2H-MoS2 and 2H-MoSe2 nanosheets can also be functionalized with iodobenzene by carrying out the reaction in the presence of a Pd0 catalyst. We have also carried out functionalization of 1T-MoS2 with pyrene, coumarin, and porphyrin derivatives. By using first-principles density functional calculations, we show that the bonding of the functional groups with the 1T phase is stronger than with the 2H phase. This is reflected in notable changes in the electronic structure of the former upon functionalization; a gap opens up in the electronic spectrum of the 1T phase. Functionalization with para-substituted benzenes leads to a change in the work function.

Graphene analogue BCN: Femtosecond nonlinear optical susceptibility and hot carrier dynamics

Third-order nonlinear absorption and refraction coefficients of a few-layer boron carbon nitride (BCN) and reduced graphene oxide (RGO) suspensions have been measured at 3.2eV in the femtosecond regime. Optical limiting behavior is exhibited by BCN as compared to saturable absorption in RGO. Nondegenerate time-resolved differential transmissions from BCN and RGO show different relaxation times. These differences in the optical nonlinearity and carrier dynamics are discussed in the light of semiconducting electronic band structure of BCN vis-à-vis the Dirac linear band structure of graphene.