90-68-6Relevant articles and documents
Solvent-free synthesis of trisphenols as starting precursors for the synthesis of calix[4]arenes using sulfonated multi-walled carbon nanotubes
Fareghi-Alamdari, Reza,Golestanzadeh, Mohsen,Zekri, Negar
, p. 3400 - 3412 (2016/05/09)
The condensation of phenol derivatives (12 substrates) with 2,6-bis(hydroxymethyl)phenols (BMP) (6 examples) is reported using sulfonated multi-walled carbon nanotubes (SO3H@MWCNTs) under solvent-free conditions as starting precursors for the synthesis of macrocyclic molecules of calix[4]arenes. The new protocol provides a series of trisphenol derivatives (21 examples) in high yields (up to 94%) and relatively short reaction times (15-120 min). Also, direct synthesis of calix[4]arenes from different trisphenols by use of the catalyst was reported (5 examples). Furthermore, the synthesized calix[4]arene was obtained using a one-pot method from simple and easily available starting materials such as p-cresol for the synthesis of 5,11,17,23-tetramethylcalix[4]arene-25,26,27,28-tetraol. Also, in this process SO3H@MWCNTs can be reused for seven runs with almost consistent efficiency and can be recovered by easy filtration.
Lubricant composition
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, (2008/06/13)
A composition comprising a) a lubricant or a hydraulic fluid and b) at least one compound of the general formula I STR1 in which x=1 or 2 and, if x=1, R is as defined for R1 or R3 --O-- or, if x=2, R is as defined for R8, and R1 and R3 are, for example, alkyl, cycloalkyl, alkenyl, phenyl, naphthyl, aralkyl or alkaryl, or alkyl, cycloalkyl, alkenyl, phenyl, naphthyl, aralkyl or alkaryl, which are monosubstituted or polysubstituted by groups from the series comprising halogen, cyano, nitro, e.g. --OCH3 or e.g. --COOCH3, or alkyl, cycloalkyl, alkenyl, aralkyl or alkaryl which are interrupted by one or more groups from the series comprising --O--, --S--, --NH--, STR2 or alkyl, cycloalkyl, alkenyl, aralkyl or alkaryl which are monosubstituted or polysubstituted by groups from the series comprising halogen, cyano, nitro, e.g. --OCH3 or e.g. --COOCH3 and interrupted by one or more groups from the series comprising --O--, --S--, --NH--, STR3 and R2 is NR4 R5, --OR6 or --SR7, and R4 and R5 are identical or different and are, for example, --H, alkyl, phenyl, naphthyl, aralkyl or alkaryl, or R4 and R5, together with the N atom linking them, form, for example, a piperidine or morpholine radical, and R6 and R7 can be alkyl which may be interrupted by one or more groups from the series comprising --O--, --S--, --NH--, STR4 or are, for example, phenyl, naphthyl, alkaryl or aralkyl, and R8 can be alkylene which may be interrupted by at least one --O-- group or alkylidene which may be interrupted by at least one --O-- group. Some of the compounds of the formula I are novel. The compositions show an improved stability towards oxidative degradation, confer protection under extreme pressures and reduce frictional wear.
3,9-carbohydrate substituted 2,4,8,10-tetraoxa-3,9-diphosphaspiro(5.5)undecane phosphite stabilizers
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, (2008/06/13)
Carbohydrate substituted phosphites of Formula I STR1 where A is a carbohydrate residue are effective stabilizers for polymers processed at elevated temperatures and subject to thermal or oxidative degradation.