Untersuchungen über organische Säuren

Abstract

Es ist durch diese Versuche also bewiesen, dafs das niederste Glied der Reihe der sogenannten Alkoholradicale sich bei Einwirkung von Chlor eben so verhalt, wie seine Homologen Aelhyl-Amy1 C& und Amy1 CloHsz, indern sich bei Vemeidnng eines Ueberschusses von Chlor vorzugsweise die Chloride der einatoniigen Radicale mit derselben Zahl von Kohlenstoffatomen und gleichzeitig in kleinerer Menge deren Substitutionsproducte bilden , und da aller Grund VOP handen ist, anzunehmen, dafs die zwischen C&, C,Hle und GO&, liegenden Glieder dieser Reihe ,sich eben so verhalten, w, is1 durch diese Bildung von Chlorathyl aus Methyl dei Weg gebahnt, aus dem einfachsten Kohlenwasserstoffe, dem Sumpfgase, nicht nur die ganze Reihe seiner Homelogen aufaubauen, sondern auch, da dieselben den Ausgangspunkt bilden kBnnen fur die grofse Gruppe der Kohlenstoflverbinduagen, in welchen man die Kohlenstoffatome in einfachster Form an einander gelagert anzunehmen hat und welche Kekulk mit dem Namen der Fettkikper bezeichnet, es ist die Mcglichkeit gegeben, diese wichtige Gruppe duroh sehr einfache Synthesen aus den Grundstoffen darznstellen.Owens College, M a n c h e s t e r , Ende WCe 1864. Untersiichungcn uber orgranische SBuren ;von Aug. Kekulk. X.Electxolyse zweibasischer %wen.-Naohdem ich beobachtet hatte, dafs der duroh Natrinmamalgsm und. der do& Zink in akalisoher L i b u q enhiriahehe Wasserstoff die Fiihigkeit besitze, sich darch dire& Addir 8Q Ke k ti ld, t%ter.wchungm

Spectroelectrochemical Exploration of Biogenic Substrates for Electrosynthesis

“…However, if the radical mechanism of Kolbe electrolysis is considered for dicarboxylic acids, it should be possible to contain cyclic and unsaturated products by double decarboxylation. Contrary to the prevailing opinion in the literature [70][71][72][73][74][75], this was shown in a mechanistic study [53]. However, it remained unclear whether this was a consecutive reaction in which the bi-radical recombines (or cyclizes) as soon as it is released, or whether the entire reaction occurs at the surface.…”

Intramolecular Biradical Recombination of Dicarboxylic Acids to Unsaturated Compounds: A New Approach to an Old Kolbe Reaction

“…Although there have been studies reporting on the ethylene 3 b formation from succinic acid 1 b , its origin was called to be largely speculative [2b] . The same applies to standalone studies concerning acetylene being produced from fumaric 1 j (trans) or maleic acid 1 k (cis), propylene from glutaric acid 1 c and propyne from citraconic acid 1 l [13,14c,24] . All of these studies lacked, however, any mention of product yields as they were primarily of qualitative nature.…”

“…Only few outdated studies investigated the direct anodic oxidation of non‐esterified dicarboxylic acids 1 . Kekulé was the first to pronounce in 1864 that unsaturated dicarboxylic acids such as fumaric acid or maleic acid were unsuitable for Kolbe type electrolysis [13] . Meticulously studying this specific reaction type around 80 years ago, Fichter et al .…”

The reception of J. H. van't Hoff's theory of the asymmetric carbon atom

“…At the advice of Mulder, Bremer later separated the inactive malic acid by the alkaloid cinchonine (43), while van't Hoff's younger brother Herminus Johannes graduated on a study of the two malic acids (his preceptor was his brother, then professor at Amsterdam) (44). Another problem was the statement of Pasteur that there exists an optically inactive succinic acid (45), which Kekule tried to prepare by the reduction of the inactive malic acid; however, without success (46) CO2H-CHOH-CH2'C02H + HBr -C02H'CHBi"CH.>'C0,H + H,0 C02H CHBr CH2 C02H + H2 -* COjH…”