A facile synthesis of 4-acylamino-tetrahydroindazoles via the Ritter reaction

A new route toward 4-acylamino- and 4-amino-substituted tetrahydroindazoles is disclosed. The title compounds are obtained in good to excellent yields in the Ritter reaction between 4-hydroxy-tetrahydroindazoles and various nitriles. The reactivity of the tetrahydroindazole-derived carbenium ion is both sufficiently high to react with trichloroacetonitrile and sufficiently selective to resist the azide functionality within its structure. The present approach adds a method to the toolbox of tetrahydroindazole chemistry and facilitates the structural modifications of the scaffold, which has found important applications in medicinal chemistry.     

Correlations: Alkylsilane property — polynomial coefficients of the adjacency matrix of the molecular graph

Based on the characteristic polynomial coefficients (CPCs) of the adjacency matrix A′ of heterogeneous molecular graphs of the molecules containing a tetravalent heteroatom >Si< (>Ge<, >Sn<), etc. in the chain, a 13-constant additive scheme for the calculation of their physicochemical properties is obtained. The structural meaning of CPCs of the adjacency matrix A′ is established. By the formula obtained the formation enthalpies Δ _f H _{gas, 298K} ⁰ of SiC _n H_2n+2 alkylsilanes not studied experimentally are calculated.     

A New Method of Preparing Copper Oxide from Dinitrourea Copper Salt

A new approach for the preparation of copper nanooxide by solvothermal decomposition of N, N′‐dinitrourea copper(II) salt in an aprotic solvent was developed. The resulting particles were studied by transmission electron microscopy, X‐ray photoelectron spectroscopy, and small‐angle X‐ray scattering. The effects of different solvents on shapes of the agglomerates formed are shown.     

5‐Amido‐ and 5‐Amino‐Substituted Epoxyisoindolo[2,1‐a]tetrahydroquinolines and 10‐Carboxylic Acids: Their Synthesis and Reactivity

The interactions between 4‐R‐substituted 2‐furyl‐1,2,3,4‐tetrahydroquinolines (synthesized by the Povarov reaction) and a number of alkenes have been investigated. Maleic, dibromomaleic, dichloromaleic, and citraconic anhydrides, as well as acryloyl, methacryloyl, crotonyl, and cynnamoyl chlorides were used as alkene components. It was shown that the initial N‐acylation of the tetrahydroquinolines was followed by a spontaneous [4+2]‐cycloaddition of an N‐acryloyl substituent to the furan ring. It was established that the intramolecular Diels–Alder reaction of furans is reversible, occurs stereoselectively as exo‐addition, and led to target epoxyisoindolo[2,1‐a]tetrahydroquinolines with moderate yields. Oxidation and aromatization of the synthesized products were carried out.     

Carbometallic derivatives of C 1v and C 5v boranes: Enumeration and identification of substitution isomers and the calculation scheme of the properties of C 5v based on pascal’s triangle numbers

Combinatorial analysis methods are employed to solve the problem of determining the number and form of X-substituted (X, XY, … are some substituents) of carbometallic derivatives of boranes (C₅H₅)Co(C₂B₉H₁₁) C _1v and (C₅H₅)Co(C₅B₆H₁₁) C _5v (over vertices) based on Polya’s theorem. formulas of Z symmetry and generating functions of the number of chiral and achiral substitution stereoisomers are determined. Family distributions of the isomers depending on the form and number of substituents and depending on the number m of possible substitution sites are found. Mono-, di-, and tri-X-substituted (X = CH₃, F, …) isomers of (C₅H₅)Co(C₅B₆H₁₁) C _5v are identified. Based on the partition of simple (n) and triangular numbers (K ₃) of Pascal’s triangle, additive schemes are obtained which take into account valence and non-valence pair interactions of atoms in the polyhedron framework and contain 2, 6, and 23 parameters for the calculation of properties of X-substituted borane (C₅H₅)Co(C₅B₆H₁₁) C _5v .     

Partial-state formalism and the object-subject split in quantum mechanics

A suitable general statistical framework is established by taking quantum mechanics as full, and other (state-distinguishing) statistical theories as partial theories with respect to a given relevant subset of observables. The partial theory exists and is unique up to equivalence. The choice of the simplest or canonical one is determined. The recently introduced hybrid, i.e., half quantum mechanical and half classical discrete, statistical states obtain thus their rightful place in a hierarchy of relevant quantum statistical theories. On the other hand, these states are shown to represent a derivation of the quantum object-subject split with a well-defined subject that encompasses preparator or measuring instrument in a natural way.