par Martin, Richard ;Vassart, Simon
Référence Bulletin des Sociétés chimiques belges, 61, 5-6, page (234-244)
Publication Publié, 1952
Article révisé par les pairs
Résumé : A new synthesis of 1:2,3:4‐dibenzfluorene (X) is described. This synthesis involves the following steps: condensation of 2‐lithium‐biphenyl (the corresponding organomagnesium derivative gave less satisfactory results) with α‐indanone and dehydration of the resulting carbinol with anhydrous potassium hydrogen sulfate to 2 (l'‐indeno) biphenyl (VIII). Yield: 29%. Cyclisation of the unsaturated hydrocarbon (VIII) by treatment, first with perphthalie acid (performic acid gave erratic results) and than with 34 % HBr in acetic acid (Bradsher's method). Yield: 8 %. This type of synthesis could be used for the preparation of benzfluorenes possessing a phenanthrene system. In the course of these experiments 1 (9′‐fluoryl) spiro‐indane (XI) was isolated as a by product. Copyright © 1952 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim