Additive Reaction

Author(s):  
Jan W. Gooch
Keyword(s):  
1953 ◽  
Vol 26 (4) ◽  
pp. 902-911 ◽  
Author(s):  
C. S. Ramakrishnan ◽  
D. Raghunath ◽  
J. B. Pande

Abstract The chlorination of rubber solutions by gaseous chlorine was followed by isolating the partially chlorinated products and preparing their ozonides. The ozonides were hydrolyzed, and the acids and aldehydes formed on hydrolysis were determined. By a comparison with the amounts of acids and aldehydes obtained from ozonides of unreacted rubber, the amount of residual isoprenic double bonds present was found. The loss of double bonds attending the introduction of chlorine atoms into the molecule of rubber indicates four definite stages in chlorination : (1) initial substitutive attack by chlorine, with concomitant cyclization, resulting in a loss of one double bond between two isoprenic units, (2) substitution, (3) additive reaction, and (4) essentially substitution. Chlorination of aged rubber solutions differs from the above in that the cyclization reaction (stage 1) seems to be absent.


2017 ◽  
Vol 17 (1) ◽  
pp. 151 ◽  
Author(s):  
Teni Ernawati ◽  
Maksum Radji ◽  
Muhammad Hanafi ◽  
Abdul Mun’im ◽  
Arry Yanuar

This paper reviews biological activity of some cinnamic acid derivative compounds which are isolated from natural materials and synthesized from the chemical compounds as an agent of α-glucosidase inhibitors for the antidiabetic drug. Aegeline, anhydroaegeline and aeglinoside B are natural products isolated compounds that have potential as an α-glucosidase inhibitor. Meanwhile, α-glucosidase inhibitor class of derivatives of cinnamic acid synthesized compounds are p-methoxy cinnamic acid and p-methoxyethyl cinnamate. Chemically, cinnamic acid has three main functional groups: first is the substitution of the phenyl group, second is the additive reaction into the α-β unsaturated, and third is the chemical reaction with carboxylic acid functional groups. The synthesis and modification of the structure of cinnamic acid are very influential in inhibitory activity against α-glucosidase.


2010 ◽  
Vol 113-116 ◽  
pp. 2053-2056
Author(s):  
Yan Wang ◽  
Rui Qing Liu ◽  
Ai Hua Wen ◽  
Xuan Dong Li

In order to avoid the damage on mesostructure by the high temperature treatment, inorganic titanium species were used as the precursors for the preparation of mesoporous TiO2 of crystalline framework at mild conditions. The influences of the precursor, additive, reaction pH and temperature on phase and textural structures of the products were investigated. The samples were characterized by XRD, N2 adsorption/desorption, FT-IR and SEM. The results show that anatase mesoporous TiO2 with large surface area could be obtained without calcination with Ti(SO4)2 as precursor or TiCl4 when SO42- was added. And the template could be completely removed by Soxhlet extraction.


Using the concept of phonon-lattice interaction, an expression is derived for the minimum temperature, T R , of a solid at which it may enter into solid-state reaction. This expression leads to a more precise idea of single-component reaction (sintering) temperatures than those given by Hüttig. Reaction between two different solids has been re-examined in the light of their physical and crystallographic properties. The rate law for such an additive reaction has been deduced from the quantum rate theory. It is concluded that crystallographic phase transformations and the formation of transitional superstructures constitute the phase-boundary processes and that the kinetics are governed by the dynamics of the diffusion process.


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