Stereospecific synthesis of (E)-alkenylpyridines via α-silyl carbanion

(E)-2-Alkenylpyridines were stereospecifically prepared from 2-(trimethylsilylmethyl)pyridine and the corresponding (E)-aldimines of anilines by an analogous reaction to the Peterson reaction.     

Deflation algorithm for the multiple roots of a system of nonlinear equations

T. Ojika, S. Watanabe, and T. Mitsui (in preparation) have been developing a subroutine package NAES (Nonlinear Algebraic Equations Solver) for the numerical solutions of the system of nonlinear equations. An algorithm, in the package, termed the deflation algorithm, for determining multiple roots for a system of nonlinear equations, is presented and its effectiveness is shown by solving a numerical example.     

Energy levels and γ-ray transitions in 147Pm

Gamma rays emitted in the decay of ¹⁴⁷Nd have been studied using Ge(Li) detectors as singles and coincidence spectrometers. Four new γ-rays of 53.1, 81.15, 149.4 and 191.24 keV have been detected and all incorporated into the decay scheme. Angular correlation measurements for the 275–319, 275–411 and 272–408 keV cascades have yielded the following result: A₂(275–319) = 0.006(2), A₄(275–319) = 0.005(5), A₂(215–411) = ?0.013(17), A₄(275–411) = ?0.008(30), A₂(272–408) = ?0.283(10) and A₄(272?408) = 0.015(18). From these coefficients the E2/M1 mixing ratios of the 272 and 275 keV γ-transitions have been determined to be 0.10(3) and 0.107(7), respectively, and the spin of the 680.43 keV level to be $\text{7}\text{2}$. Theoretical calculations on the intermediate coupling model for harmonic and anharmonic potential functions have been carried out and better agreement with experiment has been obtained for the anharmonic potential function.