Condensation Schulz

For many decades intramolecular O-coupling was considered not to take place in the diazotization products of 2-aminophenol and its derivatives (for a contrary opinion see, however, Kazitsyna and Klyueva, 1972). The compounds were assumed to be present as one structure only, which can be represented as a mesomer of a phenoxide diazonium zwitterion 6.63 b and a diazocyclohexadienone 6.63 a (see reviews by Kazitsyna et al., 1966 Meier and Zeller, 1977 Ershov et al., 1981). In IUPAC nomenclature 6.63 is called 1,2-quinone diazide, in Chemical Abstracts 6-diazo-2,4-cyclohexadien-one (see Sec. 1.3). More recently, however, Schulz and Schweig (1979, 1984) were able to identify the intramolecular product of O-coupling, i.e., 1,2,3-benzooxadiazole (6.64) after condensation of 6.63 in vacuo at 15 K in the presence of argon (see Sec. 4.2). 

The polymerisation reaction is a step growth polymerisation similar to a condensation polymerisation of amides or esters. The reaction starts with monomers, which dimerise, trimerise, etc. continuously maintaining a Flory-Schulz distribution. 

Schaefgen and Flory [79] were the first to observe this effect. They prepared star-branched polyamides by co-condensation of A-B types of monomers with central units which carried/-functional A groups. By this technique star molecules were obtained in which the arms are not monodisperse in length. They rather obeyed the Schulz-Flory most probable length distribution with polydis-persity index However, the coupling of f arms onto a star center leads... 

Equation (6) defines most of the intrinsic characteristics of the DEA process. For further information on the mechanism of transient anion formation and its effects in isolated electron-atom and electron-molecule systems, the reader is referred to the review articles by Schulz [17] and others [7,19,20]. Information on resonance scattering from single layer and submonolayer of molecules physisorbed or chemisorbed on conductive surfaces can be found in the review by Palmer et al. [21-23]. The present article provides information essentially on resonances in atoms and molecules condensed onto a dielectric surface or forming a dielectric thin film. 

Dr. Gunther Schulze describes an interesting electrolytic condenser in the Electrochemical and Metallurgical Industry, Vol. VII, page 216. The condenser is made up of ten aluminum plates 3 13/16x6/4x1/25 inches, cut as show-n in Fig. 4 and the lugs bent up (Fig. 5) to form the connections. The lugs and about half an inch of the top of the plates were placed in a saturated solution of ammonium borate, and a thick film formed at 500 volts, as indicated by the shaded area in Fig. 5. The purpose of this film is to help insulate the plate where it meets the surface of the electrolyte in the... 

The polysulfones are made by condensation polymerization of the potassium salt of bisphenol-A with dichlorodiphenyl sulfone, as discussed by S. R. Schulze and A. L. Baron. The polysulfonates are made from bisphenol-A and disulfonyl chlorides. They are more brittle than poly-sulfone and have been suggested by R. J. Schlott and co-workers to be used in coplymers with linear polyesters to improve the hydrolytic stability of the latter. 

Ganschow M., Wark M., Wohrle D. and Schulz-Ekloff G. Anchoring of functional dye molecules in MCM-41 by microwave-assisted hydrothermal co-condensation, Angew.Chem. Int. Ed, 39 (2000) pp. 161-163. 

Both chlorites and hydrotalcites performed as Fischer Tropsch catalysts, with an Anderson-Schulz-Flory value of about 0.8, as expected from the presence of metallic cobalt. Both yielded condensates consisting mainly of n-alkanes, peaking at and... 

S. R. Schulze and A. L. Baron, Addition and Condensation Polymerization Processes, Advances in Chemistry Series, 91 (1969) 692. 

In the final chapter, J. Wolf and B. Schulze (University of Leipzig, Germany) review isothiazolium salts and their use in synthesis. Many condensed S,N-hetero-cyclic systems are described in this, the first review dedicated to this topic. 

Schulze and Oediger have used such a reaction in the synthesis of piperine (26), the sharp principle of black pepper. Condensation of piperonal with N-crotonylpiperidine in DMSO in the presence of benzyl-triethylammonium hydroxide provides piperine in 80% yield (equation 91). ... 

The MMD expected for condensation polymerization (and also for free-radical polymerization with termination by disproportionation ) is the most probable (also referred to as Flory-Schulz) MM distribution ... 

HtiTTENBAUCH and Schulze [306] have proposed thermostatisation of the cover to prevent condensation of solvent on it. Ritschard [576] has used a modified BN-chamber, easily convertible into an electrophoresis chamber for preparing peptide maps (cf Wieland [757]). 

A summary of the semantics of electron molecular resonances occurring in the gas phase have been described by Schulz (1973a) (see O Table 34-2) with relevance to the condense phase. 

Johnson, D. W., Rowley, D. R., Schulze, K. H., and Carrigan, J. F., 1994, Integrated Flue Gas Treatment and Heat Recovery Using a Condensing Heat Exchanger, paper presented at the American Power Conference, Chicago, IL, April 25-27,... 

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