4- bromophenyl 4-methoxyphenyl

Pentono- and hexono-1,4-lactones yielded substituted arylhydrazides on treatment with m- and />-tolyl-, m- and p-methoxyphenyl, p-bromophenyl, and p-ethoxycarbonylphenyl-hydrazines (131). It was found that the rate of hydrazinolysis depends on the configuration of the aldonolactone, as well as on the aryl substituent on the hydrazine. 

The development of mass spectrometric ionization methods at atmospheric pressures (API), such as the atmospheric pressure chemical ionization (APCI)99 and the electrospray ionization mass spectrometry (ESI-MS)100 has made it possible to study liquid-phase solutions by mass spectrometry. Electrospray ionization mass spectrometry coupled to a micro-reactor was used to investigate radical cation chain reaction is solution101. The tris (p-bromophenyl)aminium hexachloro antimonate mediated [2 + 2] cycloaddition of trans-anethole to give l,2-bis(4-methoxyphenyl)-3,4-dimethylcyclobutane was investigated and the transient intermediates 9 + and 10 + were detected and characterized directly in the reacting solution. However, steady state conditions are necessary for the detection of reactive intermediates and therefore it is crucial that the reaction must not be complete at the moment of electrospray ionization to be able to detect the intermediates. 

HGURE 8.1. Formal potentials of redox species in W, NB and DCE versus NHE. Abbreviations ZnTMPyP = zinc tetra-7V-methyl-4-pyridium porphyrin, DcMFc = decamethylfetrocene, TCNQ = 7,7,8,8-tetracyanoquinodimethane, DiMFc = dimethylferrocene, Fc = ferrocene, RuTPP(py)2 = bisfpyridine) meso-tetraphenylporphyrinato ruthenium(II), SnPc2 = tin(IV) diphthalocyanine, LuPc2 = lutetium(in) di]dithalo-cyanine, DiFcET = diferrocenylethane, TAA = tris(4-methoxyphenyl)amine, TPB = tetraphenylborate, TBrPA = tris(4-bromophenyl)amine, TCIPB = tetrakis(4-chlorophenyl)borate. The data is from Ref. [26], except where otherwise noted Ref. [6], Ref. [29], Ref. [30], Ref. [31], Ref. [32]. Reprinted from Ref. [28], with permission from the Polarographic Society of Japan. 

Ar= Phenyl, 4-chlorophenyl, 4-bromophenyl 4-biphenyl, 2-naphthyl, 4-methoxyphenyl... 

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