Hoechst Aktiengesellschaft

Utz-Hellmuth Felcht

Eberhard Perplies

Lothar Brandt

Gerhard Buchberger

Helmut Berenbold

Josef Hilbig

Wolfgang Kornrumpf

The process for preparing water-soluble mixed cellulose ethers proceeds in the following steps:

Preparation of water-soluble mixed cellulose ethers

The novel water-soluble compounds are the ethyl ether and the N,N-dialkyl(C.sub.1 to C.sub.4)aminoethyl ethers of .beta.-cyclodextrin (.beta.-CD). The process for the preparation of these ethers is performed by reacting .beta.-CD with an etherifying agent in a basic liquid reaction medium. The reaction medium contains an alkali-metal hydroxide, water and at least one water-miscible organic solvent (for example, dimethoxyethane or isopropanol).

Ethers of beta-cyclodextrin and a process for their preparation

The invention relates to novel water-soluble mixed ethers of .beta.-cyclodextrin (.beta.-CD) with ether substituents comprising (C.sub.1 and C.sub.2) alkyl, hydroxy(C.sub.2 to C.sub.4)alkyl and carboxy(C.sub.1 and C.sub.2)alkyl such as methylhydroxyethyl-.beta.-CD or hydroxyethyl-carboxy-methyl-.beta.-CD; hydroxyethyl-hydroxy propyl ethers are excepted. The process of the invention comprises reacting .beta.-cyclodextrin with at least two different alkylating, hydroxyalkylating and/or carboxyalkylating etherifying agents (for example, methyl chloride, ethylene oxide and/or chloroacetic acid) in a basic, liquid reaction medium containing an alkali-metal hydroxide, water and, optionally, at least one organic solvent (for example, dimethoxyethane or isopropanol).

Water-soluble mixed ethers of .beta.-cyclodextrin and a process for

The process for preparing mixed cellulose ethers proceeds in the following steps:

Preparing water-soluble mixed cellulose ethers

In modern processes for the preparation of cellulose ethers containing one or more types of substituents (such as MC, CMC, HEC, HPC, MHEC or EHEC), cellulose is reacted with etherifying agents in the presence of water, base and a mixture of preferably inert organic solvents (as a dispersing auxiliary). Dimethoxyethane (ethylene glycol dimethyl ether) and at least one organic solvent selected from the group including alkanols, alkane diols and alkoxy alkanols (for example, methanol and/or isopropanol) are employed in the mixture of organic solvents used for these syntheses, particularly in quantities of 1 to 30 parts by weight per 1 part by weight of cellulose.

Preparing cellulose ethers in a dimethoxyethane/(dispersing auxiliary)

Modified cellulose reaction products, which are dispersible in aqueous media over a broad pH range without lump formation, are prepared by reacting water-soluble cellulose ether with a specified silane modifying agent in the amount of from 0.0001 to 0.12 mole of modifying agent per mole of cellulose in the cellulose ether.

Cellulose ethers having improved dispersing properties

In modern processes for preparing cellulose ethers containing one or more types of substituents, such as MC, CMC, HEC, HPC, MHEC or EHEC, cellulose is reacted with an etherifying agent in the presence of water, base and at least one inert organic solvent (as a dispersing auxiliary). Dimethoxyethane (ethylene glycol dimethyl ether) is employed as a new organic solvent for these syntheses, particularly in quantities of 1 to 30 parts by weight per part by weight of cellulose.

Dispersing auxiliary for preparing cellulose ethers

1-Halogen-1-oxo-.DELTA..sup.3 -phospholenes are produced in isomerically pure form by reacting phosphorus trihalides, 1,2-epoxides and 1,3-dienes in a molar proportion of 1 : greater than 1 : at least 1, without isolation of an intermediate stage and at elevated temperature. The process products are intermediates for the manufacture of fungicides, of additives for mineral oils and polymers and of catalysts for the manufacture of polyurethane foams.

Process for the manufacture of 1-halogen-1-oxo-.DELTA..sup.3

1-Oxo-phospholane-chlorohydrins are prepared by reacting 1-oxo-phospholenes with chlorine in the presence of bases which bond hydrogen chloride in a molar ratio of about 1:1:1 in water; the water is optionally in mixture with a water-miscible inert organic solvent. Most of the reaction products are new compounds, which are chiefly used as intermediate products in the field of plastics, of hydraulic fluids and of catalysts for converting isocyanates into carbodiimides.

Process for the preparation of 1-oxo-phospholane-chloro-hydrins

3-Acyl-2-alkyl- and 3-acyl-2-aryl-1,3,2-benzoxazaphospholanes are prepared by reacting dichlorophosphanes, 2-N-acylaminophenols and organic nitrogen bases binding hydrogen chloride in a molar proportion of about 1:1.gtoreq.2 in an inert solvent in a one stage process without isolation of an intermediate product. The compounds obtained are, for the most part, novel and are used for the manufacture of alkyl- and aryl-1-oxophospholanes, which are used as catalysts for the production of rigid polyurethane foams.

Process for the manufacture of 3-acyl-2-alkyl- and

1-Oxophosphol-.DELTA..sup.3 -enes are prepared in a one-vessel process by reacting dichlorophosphanes, 2-N-acylaminophenols, organic nitrogen bases which bind hydrogen chloride and dienes in a molar proportion of about 1:1: at least 2:(1-2)in an inert solvent witout isolation of an intermediate stage. The reaction products are used as catalysts in the production of rigid polyurethane foams, as selective metal extraction agents or as growth regulators in plant protection.

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Bruchmuhlbach, Germany

Utz-Hellmuth Felcht