摘要:
The invention relates to new optically active amino acid derivatives of the general formula (I) ##STR1## in which n, R, R.sub.1, R.sub.2, R.sub.3, X and A have the meaning given in the description, which amino acid derivatives contain sulphoxide or sulphone groups, to two basic synthetic routes for the preparation from sulphur-containing amino acids, to the polymerization of these monomers and to the use of the polymers as optically active adsorbents for chromatographic resolution of racemates to give the enantiomers.
摘要:
The invention relates to new optically active sulphur-containing amino acid derivatives, a process for their preparation, their polymerisation to give optically active polymers and the use of these optically active polymers as adsorbents for chromatographic separation of racemates into enantiomers.
摘要:
The invention relates to optically active, pressurestable bead polymers containing fillers, and their use as adsorbents for the chromatographic resolution of enantiomeric mixtures (or racemates) into their enantiomers.
摘要:
The present invention relates to a process for the enantiomeric enrichment of cis-8-benzyl-7,9-dioxo-2,8-diazabicyclo[4.3.0]nonane with the aid of continuous countercurrent chromatography, which is also described as SMB chromatography (SMB=simulated moving bed).In a further aspect, the invention relates to a process for the preparation of (1S,6R)-8-benzyl-7,9-dioxo-2,8-diazabicyclo[4.3.0]nonane using the aforementioned process, which furthermore includes a racemization step.
摘要:
Polyhalogenated cinnamic acids and cinnamic acid derivatives are prepared by reacting diazonium salts accessible from polyhalogenated anilines with acrylic acid or acrylic acid derivatives in the presence of a homogeneous, palladium-containing catalyst at about −5 to about +100° C. Some of the cinnamic acids and cinnamic acid derivatives obtainable in this way are new. Cinnamic acids and cinnamic acid derivatives which can be prepared according to the invention can be used for the preparation of indanones which are precursors for agro- and pharmaceutical chemicals and for substances having liquid-crystalline properties.
摘要:
A method for detecting failures in an analog-to-digital converter includes monitoring a series of outputs from an analog-to-digital converter and detecting a failure in the analog-to-digital converter when a specified number of consecutive outputs comprise a same value.
摘要:
The invention relates to the preparation and use as catalysts of diphosphines of the formula (I) in which R is C6-C14-aryl or C4-C13-heteroaryl containing 1 to 3 heteroatoms selected from the group consisting of nitrogen, oxygen, and sulfur, wherein the aryl and heteroaryl radicals may optionally be substituted by halogen, C1-C6-alkyl, C1-C6-alkoxy, and/or trimethylsilyl, and R1 to R4, independently of one another, are each hydrogen, C1-C10-alkyl, C1-C10-alkoxy, F, Cl, or Br.
摘要:
The invention relates to substituted cinnamic acids and cinnamic acid esters of formula (I), wherein X represents F, Cl or J and R1 and R2 are the same or different and represent hydrogen, an optionally substituted C1-C10-alkyl radical or an optionally substituted benzyl radical. Substituted indanone carboxylic acid esters are produced using said substituted cinnamic acid and cinnamic acid ester in a technically simple and non-dangerous manner as far as safety is concerned.
摘要:
The invention relates to a process for the preparation of nitrosobenzenes from aromatic amines by oxidation with hydrogen peroxide in the presence of sodium molybdate dihydrate and an inert organic solvent.
摘要:
The invention relates to a process for the preparation of nitrodiphenylamines by reaction of nitrohalogenobenzenes with aromatic amines in the presence of a palladium catalyst and a base, the base being ground and/or dried before its use.