Convenient synthesis of 2-benzazepines via radical cyclization

Synthesis of 2-benzazepines was readily achieved via 7-endo radical cyclization of N-o-bromobenzylitaconamides or N-o-bromobenzylmethacrylamides which were prepared in two steps from commercially available benzaldehydes, amines, and alpha,beta-unsaturated acids.     

Negative‐working photoresist based on a first‐generation dendrimer consisting of 4,4‐diphenylpentyloxy units

A first‐generation dendrimer ( 2 ), containing phenol groups in the exterior for solubilization in aqueous alkaline solutions, was evaluated as a new negative‐working, alkaline‐developable photoresist material. A negative‐working photoresist based on 2 , 4,4′‐methylenebis[2,6‐bis(hydroxymethyl)phenol] as a crosslinker, and diphenyliodonium 9,10‐dimethoxyanthracene‐2‐sulfonate as a photoacid generator was demonstrated. This resist gave a clear negative pattern through postbaking at 90 °C after exposure to UV light, which was followed by development with a 2.38% aqueous tetramethyl ammonium hydroxide solution at room temperature. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1210–1215, 2005     

Redox-Neutral Tetrafluoroethylation of Aryl Alkynes with 1,1,2,2-Tetrafluoroethane Sulfonic Acid Leading to α-Tetrafluoroethylated Acetophenones

The redox-neutral tetrafluoroethylation of alkynes with 1,1,2,2-tetrafluroroethanesulfonic acid (TFESA) and azobis(isobutyronitrile) (AIBN) proceeds via the formation of vinyl tetrafluoroethanesulfonates followed by a radical tetrafluoroethylation. Experimental and theoretical results support an intermolecular reaction.     

Four-Body Structure of Λ Hypernuclei and 4He Tetramer System

Gaussian Expansion Method has been applied to four-body calculations of ${^4_{\Lambda}{\rm H}}$ and ${^4_{\Lambda}{\rm He}}$ , and four-body calculation of ⁴He tetramer. We found that Λ N? Σ N coupling is important to make bound A = 4 hypernuclei. The binding energies of the tetramer ground state and excited states are obtained as 558.98 and 127.33 mK.     

Determination of antiproton mass from the calculation of energy levels of antiprotonic helium atoms

We calculate the energy levels of the metastable states of an antiprotonic helium atom. The coupled rearrangement channel method is employed to describe a dual character of the atom effectively. Calculated transition frequencies between the metastable states are in good agreement with the observed values. The uncertainty of an antiproton mass is estimated by the calculated transition frequencies with the slightly shifted antiproton mass from the proton mass. When a more accurate value of the charge-to-mass ratio of antiproton is considered, the uncertainty of antiproton mass and charge is estimated at 54 ppb which improves the value recommended by the particle data by a factor of ten.     

Study of various few-body systems using Gaussian expansion method (GEM)

We review our calculation method, Gaussian expansion method (GEM), to solve accurately the Schrödinger equations for bound, resonant and scattering states of few-body systems. Use is made of the Rayleigh-Ritz variational method for bound states, the complex-scaling method for resonant states and the Kohn-type variational principle to S-matrix for scattering states. GEM was proposed 30 years ago and has been applied to a variety of subjects in few-body (3- to 5-body) systems, such as 1) few-nucleon systems, 2) few-body structure of hypernuclei, 3) clustering structure of light nuclei and unstable nuclei, 4) exotic atoms/molecules, 5) cold atoms, 6) nuclear astrophysics and 7) structure of exotic hadrons. Showing examples in our published papers, we explain i) high accuracy of GEM calculations and its reason, ii) wide applicability of GEM to various few-body systems, iii) successful predictions by GEM calculations before measurements. The total bound-state wave function is expanded in terms of few-body Gaussian basis functions spanned over all the sets of rearrangement Jacobi coordinates. Gaussians with ranges in geometric progression work very well both for shortrange and long-range behavior of the few-body wave functions. Use of Gaussians with complex ranges gives much more accurate solution than in the case of real-range Gaussians, especially, when the wave function has many nodes (oscillations). These basis functions can well be applied to calculations using the complex-scaling method for resonances. For the few-body scattering states, the amplitude of the interaction region is expanded in terms of those few-body Gaussian basis functions.     

Asymptotic form of three-body (dtµ)+ and (ddµ)+ wave functions

In order to investigate a discrepancy between existing literature values for the normalization constant in the asymptotic form of three-body wave functions for (dtµ)⁺, we report the results of a new calculation of the normalization constants for this system as well as the related system (ddµ)⁺. These were obtained by fitting to accurate variational wave functions with special care being taken to describe the long-range behavior.     

Transition densities between the 01+, 21+, 41+, 02+, 22+, 11− and 31− states in 12C derived from the three-alpha resonating-group wave functions

All the multipole transition densities between the seven T = 0 states in ¹²C are calculated with the use of the microscopic 3α resonating-group wave functions which are obtained by dynamically solving the 3α relative motion with the total antisymmetrization taken into account exactly. The observed elastic and inelastic electron scattering form factors for the transition to the 2₁⁺, 4₁⁺, 0₂⁺, 1₁^?and 3₁^? states are well reproduced with no additional effective charge. The existence of a deformed intrinsic state for the 0₁⁺, 2₁⁺and 4₁⁺states is deduced by the analysis of the transition densities between them which are derived by the weak-coupling-type 3α wave functions; the intrinsic density distribution is illustrated. The monopole density distribution of the 0₂⁺, 2₂⁺ and 1₁^?, states is found to be much longer ranged than that of the 0₁⁺, 2₁⁺ and 4₁⁺ states; the 3₁^? state case is intermediate. On the basis of the transition densities between the 0₁⁺, 2₁⁺, 0₂⁺ and 2₂⁺ states, analysis is made of the transition between the shell-like states and the molecule-like states with a large spatial-structure change. Specific, effective nucleon-nucleon interactions are folded into the transition densities here obtained. The evident dependence of the radial shape of the folded nucleon-¹²C form factors on the choice of the interactions and the multi-step form factors for the excitation of the 0₂⁺, 1₁^? and 3₁^? states are discussed.     

Synthesis and characterization of cyclotetraphosphato complexes of Rh(I), Ir(I), Ru(II), and Pd(II)

The cyclotetraphosphate ion (P(4)O(12)(4)(-)) as a PPN (PPN = (PPh(3))(2)N(+)) salt reacts with [MCl(cod)](2) (M = Rh, Ir; cod = 1,5-cyclooctadiene) to give the dinuclear complexes (PPN)(2)[[M(cod)](2)(P(4)O(12))], in which the two metal moieties are situated trans to each other with respect to the P(4)O(4) ring in the solid state. In solution, however, these complexes exist as mixtures of trans and cis isomers. On the other hand, the P(4)O(12)(4)(-) ion reacts with 4 equiv of [Rh(cod)(MeCN)(x)](+) cation to give the tetranuclear complex [[Rh(cod)](4)(P(4)O(12))], where the four Rh(cod) fragments are bound to the P(4)O(12) platform alternately on both sides of the P(4)O(4) ring. Dinuclear P(4)O(12) complexes of ruthenium and palladium are also synthesized.