Abstract: The present invention relates to cyclic siloxanes which have at least one group of formula (1) bonded to a silicon atom--(CH.sub.2).sub.x --R"--[--L--A--].sub.y --(L).sub.z --T (1),in which x is an integer having a value of at least 2, preferably having a value of from 2 to 10, R" is a chemical bond or a divalent radical of the formula --COO--, --OOC--, --CH.sub.2 --CH.sub.2 --, --CH.dbd.CH--, --C.tbd.C--, --N.dbd.N--, --N.dbd.N, --N.dbd.CH--, --CH.dbd.N or --Si(R).sub.

Abstract: The invention relates to optical elements based on helical liquid-crystalline substances, having reflection bands of linear-polarized light, and to a process for preparing the same. The optical elements of this invention contain only one optically effective component based on helical liquid-crystalline substances. They reflect light incident perpendicular to the surface in a linear-polarized manner parallel to the direction of incidence of the incident light. The process for preparing the optical elements comprises illuminating a helical liquid-crystalline substance which contains at least one photoisomerizable substance with linear-polarized light in such a manner that this substance is subsequently aligned so that it exhibits at least one reflection band of linear-polarized light on illumination. Suitable helical liquid-crystalline substances are in particular organopolysiloxanes. The optical elements are suitable, for example, for data storage.

Abstract: The invention relates to compounds of the formula ##STR1## in which R.sup.3 is a hydrogen atom or a radical of the formulaR.sup.1 --R.sup.5 --O--(CH.sub.2).sub.y --,in which R.sup.1 is a halogen atom, a hydroxyl group, a C.sub.1 - to C.sub.18 -alkoxy group, a C.sub.1 - to C.sub.18 -alkyl group or a cholesteryl radical, R.sup.5 is a phenylene or biphenylene radical which may be linked to a phenylene radical via the --OOC-- group or a phenylene radical linked the --OOC-- group, y is an integer of from 3 to 12, R.sup.2 is selected from the group consisting of a radical of the formulaR.sup.6 --R.sup.1 and R.sup.7 --SiCH.sub.3).sub.2 H,where R.sup.6 is a single chemical bond or a phenylene, biphenylene or cyclohexylene racial or a phenylene radical linked to the --OOC-- or --COO-- radical or a phenylene radical linked to a cyclohexyl radical through the --OOC-- group, R.sup.

Abstract: Cyclic organosiloxanes which contain at least one Si-bonded organic radical and have at least one donor/acceptor .pi.-electron system.

Abstract: The present invention relates to cyclic siloxanes which have at least one group of formula (1) bonded to a silicon atom--(CH.sub.2).sub.x --R"--[--L--A--].sub.y --(L).sub.z --T (1),in which x is an integer having a value of at least 2, preferably having a value of from 2 to 10, R" is a chemical bond or a divalent radical of the formula --COO--, --OOC--, --CH.sub.2 --CH.sub.2 --, --CH.dbd.CH--, --C.tbd.C--, --N.dbd.N--, --N.dbd.N(O)--, --CH.dbd.N--, --N.dbd.CH--, --N.dbd.N--, --N.dbd.N(O)--, --N.dbd.CH--, --CH.dbd.N--, or --Si(R).sub.

Abstract: The present invention relates to liquid-crystalline compounds and to a process for preparing liquid-crystalline polyorganosiloxanes having methacryloxy and/or acryloxy groups by the reaction of organosiloxanes having hydrogen atoms bonded directly to silicon atoms and/or organosilanes which can be condensed to form organosiloxanes having hydrogen atoms bonded directly to silicon atoms, with alkenes and/or alkynes having mesogenic groups, which comprises reacting in a first step the organosiloxanes with an alkene and/or alkyne having at least one non-enolic hydroxyl group protected by a protective group, and in a second step the protective group is removed and the hydroxyl group which is now free is esterified with (meth)acrylic acid, esters, anhydrides and/or halides thereof and thereafter optionally condensing the organosilanes to organosiloxanes.

Abstract: The present invention relates to compounds of the formula ##STR1## in which Y represents an organosilicon radical;R" represents a divalent radical which connects the radical Y to the benzene ring via a chain of at least three atoms;X represents a radical of the formula --COOH, --CN, --CHO, --NH.sub.2 or --OH, in which it is possible to block the hydroxyl group with a protecting group;Z represents the same or different substituents in the 2-, 3-, 5- or 6-position to the radical X, preferably hydrogen or halogen atoms; andp represents a value of 0 to 4;and the use of these and related compounds in the preparation of compounds having liquid-crystalline properties.

Abstract: Poly(arylenevinylenesilicon) compounds and a process for their preparation, where .alpha.,w-dialkenylarylenevinylene is reacted with an organosilicon compound containing two Si-bonded hydrogen atoms, in the presence of a catalyst which promotes the addition reaction of Si-bonded hydrogen to an aliphatic multiple bond.

Abstract: The present invention relates to compounds of the formula ##STR1## in which Z is a radical bonded to the benzene ring in the 2-, 3-, 5- or 6-position, namely a halogen atom, a cyano group or a hydroxyl group,n is 0, 1 or 2,R" is a radical of the formulaR'''--[Si(R*).sub.2 ](CH.sub.2).sub.y R""-- (9),in whichY is an integer from 4 to 18,R''' is as defined in the description,R* is identical or different, optionally substituted C.sub.1 - to C.sub.18 -hydrocarbon or hydrocarbonoxy radicals,R"" is a radical of the formula --(E).sub.z -- which is optionally bonded to the carboxy group via a phenylene or biphenylene radical, whereE is a divalent radical of the formula --O-- or --Si(R*).sub.2 --, andZ is the number 0 or 1, and the radicalR' is a halogen atom, a cyano radical, a cholesteryl radical, a radical as defined for R* or of the formula --C.sub.6 H.sub.4 --R**, andR** may have any meaning of R*, with the exception of an n-octyloxy or an n-decyloxy radical,and the preparation and use thereof.

Abstract: The present invention relates to compounds of the formula ##STR1## in which Z is a halogen atom, a cyano group or a hydroxyl group,n is 0, 1 or 2,R' is a radical of the formulaR'"--[Si(R*).sub.2 ].sub.x (CH.sub.2).sub.y R""-- (9),in whichx is the number 0 or 1,y is an integer from 1 to 18,R'"is a defined in the description,R* is identical or different, optionally substituted C.sub.1 - to C.sub.18 -hydrocarbon or hydrocarbonoxy radicals,R"" is a phenylene or biphenylene radical or a radical of the formula --E--, whereE is a divalent radical of the formula --O-- or --[Si(R*).sub.2 ].sub.z --, andz is the number 0 or 1,and the compounds contain at least one group of the formula --Si(R*).sub.2 -- per molecule, and the radicalR" is a cholesteryl radical, a radical as defined for R* or a radical of the formula --C.sub.6 H.sub.4 --R*,and the preparation and use thereof.

Abstract: The invention relates to cholesteric organic polymers which contain, in the side groups, both mesogens, at least some of which are optically active, and chromophoric groups.

Abstract: A process for preparing poly-(imidesiloxanes) which comprises reacting an N,N'-dialkenyldiimide with an organosilicon compound containing two Si-bonded hydrogen atoms in the presence of a catalyst which promotes the addition of Si-bonded hydrogen to an aliphatic multiple bond.

Abstract: The invention relates to dimethylsilyl-substituted benzoyl chlorides and a process for preparing the same, which comprises reacting a dihaloaromatic compound with dimethylchlorosilane and magnesium by the Grignard method to form halophenyldimethylsilanes, then reacting the halophenyldimethylsilanes with magnesium in the presence of carbon dioxide to form the corresponding dimethylsilyl-substituted benzoic acids, and thereafter reacting the dimethylsilyl-substituted benzoic acids with a halogenating agent, such as thionyl chloride, to form dimethylsilyl-substituted benzoyl chlorides.

Abstract: Hexamethylcyclotrisiloxane is prepared by heating linear, branched, or cross-linked organopolysiloxanes containing at least 50 mol percent of dimethylsiloxane units to at least 350.degree. C. in the absence of substances which attack the siloxane group during heating and simultaneously distilling off the cyclic dimethylpolysiloxanes thus formed.The hexamethylcyclotrisiloxane thus prepared is an excellent carrier for fragrant materials, especially where the carrier is present in admixture with other carrier substances such as tetramethylcyclobutanedione.

Abstract: A solid which contains a fragrant substance and/or a disinfectant and at least one sublimable substance, in which the sublimable substance consists at least in part of hexamethylcyclotrisiloxane and/or tetramethylcyclobutanedione. When the solid is exposed to the environment, it releases the fragrant substance and/or disinfectant.

Abstract: Trialkanoyloxysilanes of the formula IR.sup.1 --A.sup.1 --A.sup.2 --O--C.sub.n H.sub.2n --Si(OOCR.sup.2) 3 Iwherein R.sup.1 is H or an alkyl group of 1-10 c atoms, wherein one or two non-adjacent CH.sub.2 groups may also be replaced by oxygen atoms, or is F, Cl, Br or CN, R.sup.2 is an alkyl group of 1-5 atoms, A.sup.1 and A.sup.2 are each 1,4-phenylene or 1,4-cyclohexylene groups and n is 2, 3, 4, 5 or 6, can be used for generating a homeotropic orientation of liquid-crystalline phases on surfaces.

Abstract: A process for producing cycloalkadienes in liquid phase by metathesis reaction of cycloalkenes in the presence of a carrier catalyst based on Re.sub.2 O.sub.7 /Al.sub.2 O.sub.3. The cycloalkenes in the form of 0.01 to 0.05 molar solutions are contacted with the carrier catalyst in a fixed bed arrangement with contact times of 10 to 100 seconds.

Abstract: Hexamethylcyclotrisiloxane is prepared by heating linear, branched, or cross-linked organopolysiloxanes containing at least 50 mol percent of dimethylsiloxane units to at least 350.degree. C. in the absence of substances which attack the siloxane group during heating and simultaneously distilling off the cyclic dimethylpolysiloxanes thus formed.The hexamethylcyclotrisiloxane thus prepared is an excellent carrier for fragrant materials, especially where the carrier is present in admixture with other carrier substances such as tetramethylcyclobutanedione.

Abstract: This invention relates to silanes of the general formulaR.sub.n Si(OCR.sub.2.sup.1 COZR).sub.4-nwhere R represents the same or different monovalent hydrocarbon radicals or substituted monovalent hydrocarbon radicals, R.sup.1 is hydrogen or the same as R, Z is oxygen or the group ##STR1## where R.sup.1 is the same as above, n is 0 or 1 and oligomers thereof. These silanes are prepared by reacting silanes of the general formulaR.sub.n SiX.sub.4-nwhere R and n are the same as above and X represents the same or different hydrolyzable atoms or condensable groups other than RCOCR.sub.2.sup.1 CO groups, with alpha-hydroxycarboxylic acid esters or amides. The silanes, which have at least three condensable groups per molecule, may be mixed with a diorganopolysiloxane containing terminal condensable groups and at least one additional substance to prepare compositions which are storage-stable under anhydrous conditions, but crosslink when exposed to moisture at room temperature to form elastomers.

Abstract: This invention relates to silanes of the general formulaR.sub.n Si(OCR.sub.2.sup.1 COZR).sub.4-nwhere R represents the same or different monovalent hydrocarbon radicals or substituted monovalent hydrocarbon radicals, R.sup.1 is hydrogen or the same as R, Z is oxygen or the group ##STR1## where R.sup.1 is the same as above, n is 0 or 1 and oligomers thereof. These silanes are prepared by reacting silanes of the general formulaR.sub.n SiX.sub.4-nwhere R and n are the same as above and X represents the same or different hydrolyzable atoms or condensable groups other than RCOCR.sub.2.sup.1 CO groups, with alpha-hydroxycarboxylic acid esters or amides. The silanes, which have at least three condensable groups per molecule, may be mixed with a diorganopolysiloxane containing terminal condensable groups and at least one additional substance to prepare compositions which are storage-stable under anhydrous conditions, but crosslink when exposed to moisture at room temperature to form elastomers.