Eistert

Arndt-Eistert synthesis A procedure for converting a carboxylic acid to its next higher homologue, or to a derivative of a homologous acid, e.g. ester or amide. 

The Arndt-Eistert reaction is a comparatively simple method for converting an acid Into its next higher homologue or to a derivative of the homologous acid, such as an amide or an ester. The overall yield is generally good. The reaction... 

An ethereal solution of diazomethane free from alcohol may be prepared as follows such a solution is required, for example, in the Amdt-Eistert reaction with acid chlorides (compare Section VI,17). In a 100 ml. longnecked distilling flask provided with a dropping funnel and an efficient downward condenser, place a solution of 6 g. of potassium hydroxide in... 

Acetoacetic ester condensation Amdt-Eistert reaction Bart reaction. ... 

Among the authors whose contribution has been important in the past, either by their experimental work or by their theoretical approach, the names of Koenig. Hamer, Fischer. Brooker, Kiprianov, Sklar, Schwarzen-bach, Eistert, Dimroth, and Platt are well familiar to scientists having an interest in the field of methine dyes, as well as more recently those of Kuhn, Wizinger, Scheibe, Hiinig, Van Dormael, Dahne, and Fabian. 

IsothiazoIe-5-carboxyIic acid, 3-methyI-bromination, S, 58 Isothiazolecarboxylic acid chlorides Amdt-Eistert reaction, 6, 157 Reissert reactions, 6, 157 Isothiazolecarboxylic acids esters... 

ARNDT EISTERT Homoiogation Homologalion of carboxylic acids or ketones... 

Rearrangement (ring contraction) of a-diazokelones to cartioxylic adds or their derivatives (esters, amides) via ketenes (see also Amdt-Eistert). 

Organometallics, such as dialkyl zinc or cadmium-alkyl or aryl lithium Alkali acetylides Diels-Alder Arndt-Eistert... 

Arndt-Eistert reaction is used to convert an acid compound into the next higher homologue by reaction with diazomethane... 

The position of the keto group of A-homo-5a-cholestan-3-one (5b) was determined by Nelson and Schut by an unambiguous synthesis of ketone (5b) involving bis-homologation of 2,3-seco-5a-cholestane-2,3-dioic acid (8) using the Arndt-Eistert sequence [(9) (11)]. 

B. Eistert, in Newer Methods of Preparative Organic Chemistry, Wiley-Interscience, New York, 1948, pp. 513flf. 

General accounts of prototropic tautomerism have been presented by Ingold and Baker" these include an outline of the historical development of the subject in which heteroaromatic compounds are discussed incidentally, and, therefore, such a historical account will not be given here. Of historical interest are Eistert s book on tautomerism and mesomerism which was published in 1938, a review on — NH-CO— tautomerism by Arndt and Eistert published in 1938, and Heller s account of heterocyclic tautomerism which appeared in 1925. Although more recent works on heterocyclic chemistry (e.g., references 9-11) have dealt incidentally with tautomerism, no unified... 

B. Eistert, Tautomerie und Mesomerie. Enke, Stuttgart, Germany, 1938. 

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