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A stirred BZ reaction mixture showing changes in color over time. The discovery of the phenomenon is credited to Boris Belousov.In 1951, while trying to find the non-organic analog to the Krebs cycle, he noted that in a mix of potassium bromate, cerium(IV) sulfate, malonic acid, and citric acid in dilute sulfuric acid, the ratio of concentration of the cerium(IV) and cerium(III) ions ...
Taking star polymers as an example, RAFT differs from other forms of living radical polymerization techniques in that either the R- or Z-group may form the core of the star (See Figure 10). While utilizing the R-group as the core results in similar structures found using ATRP or NMP, the ability to use the Z-group as the core makes RAFT unique.
An electron donating group (EDG) or electron releasing group (ERG, Z in structural formulas) is an atom or functional group that donates some of its electron density into a conjugated π system via resonance (mesomerism) or inductive effects (or induction)—called +M or +I effects, respectively—thus making the π system more nucleophilic.
A specific example of a M-Z bond wherein other L-ligands are present in the complex [7] Both uncharged transition metal complexes and anionic complexes lead to the required adducts with acidic boranes. On the right is a typical reaction of a Z-ligand where the electron deficit BPh 3 adds to the anionic Fe complex.
An examples of negative solvatochromism is provided by 4-(4 ′ -hydroxystyryl)- N -methylpyridinium iodide , which is red in 1-propanol , orange in methanol , and yellow in water . Positive solvatochromism corresponds to a bathochromic shift (or red shift) with increasing solvent polarity.
Each group is named by Small Groups library as G o i, where o is the order of the group, and i is the index used to label the group within that order.. Common group names: Z n: the cyclic group of order n (the notation C n is also used; it is isomorphic to the additive group of Z/nZ)
The protecting group is abbreviated Cbz or Z (in honor of discoverer Zervas), hence the alternative shorthand designation for benzyl chloroformate as Cbz-Cl or Z-Cl. Benzyloxycarbonyl is a key protecting group for amines , suppressing the nucleophilic and basic properties of the N lone pair .
A (Z)-group is a group faithfully represented as a doubly transitive permutation group in which no non-identity element fixes more than two points. A (ZT)-group is a (Z)-group that is of odd degree and not a Frobenius group , that is a Zassenhaus group of odd degree, also known as one of the groups PSL(2,2 k +1 ) or Sz(2 2 k +1 ) , for k any ...