公开(公告)号：DE2960041D1

公开(公告)日：1981-02-05

申请号：DE2960041

申请日：1979-02-19

Applicant: BASF AG

Inventor： PAUST JOACHIM DR ,  SCHMIDT WOLFRAM DR

IPC: C07D307/32 ,  C07D307/33

Abstract: Pantolactone is extracted from its aqueous solutions using methyl tert.-butyl ether as the extractant.

公开(公告)号：DE3460107D1

公开(公告)日：1986-06-05

申请号：DE3460107

申请日：1984-01-18

Applicant: BASF AG

Inventor： ERNST HANSGEORG DR ,  SCHMIDT WOLFRAM DR ,  PAUST JOACHIM DR

IPC: C07D475/14 ,  C07D475/02

公开(公告)号：DE3302497A1

公开(公告)日：1984-07-26

申请号：DE3302497

申请日：1983-01-26

Applicant: BASF AG

Inventor： ERNST HANSGEORG DR ,  SCHMIDT WOLFRAM DR ,  PAUST JOACHIM DR

IPC: C07D475/14 ,  C07D475/02 ,  C07D487/04

公开(公告)号：DE3163748D1

公开(公告)日：1984-06-28

申请号：DE3163748

申请日：1981-07-09

Applicant: BASF AG

Inventor： SCHMIDT WOLFRAM DR ,  PAUST JOACHIM DR ,  NUERRENBACH AXEL DR

IPC: C07C67/00 ,  C07C215/10 ,  C07C241/00 ,  C07C245/08 ,  C07D475/00 ,  C07D475/14 ,  C09B29/085 ,  C07C107/00

Abstract: A process for the preparation of N-(D)-ribityl-2-phenylazo-4,5-dimethylaniline (I), wherein 1. in the case of pure or virtually pure (D)-ribose (III) (a) the latter is reacted with 3,4-dimethylnitrobenzene (IVa) or 3,4-dimethylaniline (IVb) and with hydrogen in the presence of a hydrogenation catalyst, (b) the resulting solution is reacted, in a conventional manner, with an acid phenyldiazonium salt solution (VI) and (c) the resulting product is isolated by crystallization, in a conventional manner, or 2. in the case of crude ribose, ie. industrial mixtures of (D)-ribose and other sugars (a) the crude ribose is reacted with about equimolar amounts, based on III, of 3,4-dimethylaniline (IVb) and boric acid, (b) the boric acid ester of the Schiff base obtained from III and IVb is allowed to crystallize out and is separated off, (c) this ester is hydrogenated with hydrogen in the presence of a hydrogenation catalyst, (d) the solution is freed from catalyst and reacted, in a conventional manner, with an acid phenyldiazonium salt solution and (e) the resulting product I is isolated by crystallization in a conventional manner.