Di-tert butyl peroxide

FLUORINECOMPOUNDS,ORGANIC - FLUORINATED ALIPHATIC COMPOUNDS] (Vol 11) Perfluoro-di-tert-butyl peroxide [2684285-3]... 

Di-tert-butyl peroxide (tert-butyl peroxide) [110-05-4] M 146.2, d 0.794, n 1.389. Washed with aqueous AgN03 to remove olefinic impurities, water and dried (MgS04). Freed from /cr/-butyl hydroperoxide by passage through an alumina column [Jackson et al. J Am Chem Soc 107 208 1985], and if necessary two high vacuum distns from room temp to a liquid-air trap [Offenbach and Tobolsky J Am Chem Soc 79 278 1957]. The necessary protection from EXPLOSION should be used. 

High molecular weight polymers are produced by an adiabatic bulk polymerisation process ° using di-tert-butyl peroxide (0.02%) and 2,2 -azo-bisdi-isobutyronitrile (0.01%) as initiators and pressurised with N2. Heating to 80-90°C causes an onset of polymerisation and a rapid increase in temperature. After the maximum temperature has been reached the mass is allowed to cool under pressure. A typical current commercial material (Luvican M.170) has a A -value of about 70 (as assessed in a 1% tetrahydrofuran solution). 

DTBP see DI-tert-BUTYL PEROXIDE DURSBAN see CHLORPYRIFOS... 

The reaction of benzyl radicals wdth several heterocyclic compounds W as more extensively studied by Waters and Watson, " - who generated benzyl radicals by decomposing di-tert-butyl peroxide in boiling toluene. The products of the reaction with acridine, 5-phenyl-acridine, 1 2- and 3 4-benzacridine, and phenazine were studied. Acridine gives a mixture of 9-benzylacridine (17%) (28) and 5,10-dibenzylacridan (18%) (29) but ho biacridan, w hereas anthracene gives a mixture of 9,10-dibenzyl-9,10-dihydroanthracene and 9,9 -dibenzyl-9,9, 10,10 -tetrahydrobianthryl. This indicates that initial addition must occur at the meso-carbon and not at the nitrogen atom. (Similar conclusions were reached on the basis of methylations discussed in Section III,C.) That this is the position of attack is further supported by the fact that the reaction of benzyl radicals with 5-... 

Auch einfache aliphatische Lactone werden radikalisch nach Initiierung mit y-Strahlen oder mit photoinduzierter Zersetzung von Di-tert.-butyl-peroxid durch Trichlor-silicium-hydrid zu cyclischen Athern reduziert11 ... 

Atheraus Lactonen allgemeine Arbeitsvorschrift1 4 mMol Trichlor-siliciumhydrid und 1 mMol Laeton bzw. das Gemisch von 1 mMol Laeton und 0,05 Mol Di-tert.-butyl-peroxid werden in ciner evakuierten Glasrohre durch y-Strahlen aus einer "Co-Quelle bzw. mit U V-Licht aus einer Quecksilber-Mitteldruck-Lampe bei 20° be-strahlt. 

Note The contrast between the colored zones and the layer background can be improved by warming the chromatogram gently [4]. Di-tert-butyl peroxide does not react [3]. N,N,N, N -tetramethyl-p-phenylenediamine (q.v.) can also be used instead of N,N-DPDD for the detection of peroxides [3]. The spray solution for peroxides gradually turns dark red in color but it still retains its ability to react for several weeks [4]. 

Di-terf-butyl malonate, 59, 66 Di-tert-butyl peroxide, 55, 61... 

Experimental set up as in section a). Alkoxy radicals were produced by photolysis of di-tert.-butyl peroxide (2 Mol/1). The build up of hydroperoxide concentration was measured by a modified version of the iodometric method used by Carlsson and Wiles—. 

Biesenberger, J. A. et al., Polym. Eng. Sci., 1976, 16, 101-116 The parameters were determined in a batch reactor for thermal runaway polymerisation of styrene, initiated by azoisibutyronitrile, dibenzoyl peroxide or di-tert-butyl peroxide. 

Two types of addition to pyrimidine bases appear to exist. The first, the formation of pyrimidine photohydrates, has been the subject of a detailed review.251 Results suggest that two reactive species may be involved in the photohydration of 1,3-dimethyluracil.252 A recent example of this type of addition is to be found in 6-azacytosine (308) which forms a photohydration product (309) analogous to that found in cytosine.253 The second type of addition proceeds via radical intermediates and is illustrated by the addition of propan-2-ol to the trimethylcytosine 310 to give the alcohol 311 and the dihydro derivative 312.254 The same adduct is formed by a di-tert-butyl peroxide-initiated free radical reaction. Numerous other photoreactions involving the formation by hydrogen abstraction of hydroxyalkyl radicals and their subsequent addition to heterocycles have been reported. Systems studied include 3-aminopyrido[4,3-c]us-triazine,255 02,2 -anhydrouri-dine,256 and sym-triazolo[4,3-fe]pyridazine.257 The photoaddition of alcohols to purines is also a well-documented transformation. The stereospecific addition of methanol to the purine 313, for example, is an important step in the synthesis of coformycin.258 These reactions are frequently more... 

DHBP 2,5-Dimethylhexane-2,5-di-tert.-butyl peroxide 0.88 (liquid) 1.50 (paste powder)... 

From an experimental viewpoint, there are strong indications that the reduction of di-tert-butyl peroxide proceeds with a significant degree of non-adiabaticity.201... 

Synthetic applications of carbon radical additions to allenes cover aspects of polymerization, selective 1 1 adduct formation and homolytic substitutions. If heated in the presence of, e.g., di-tert-butyl peroxide (DTBP), homopolymerization of phenylal-lene is observed to provide products with an average molecular weight of 2000 (not shown) [58]. IR and 1H NMR spectroscopic analyses of such macromolecules point to the preferential carbon radical addition to CY and hence selective polymerization across the 2,3-double bond of the cumulene. Since one of the olefinic jr-bonds from the monomer is retained, the polymer consists of styrene-like subunits and may be... 

The reaction of EtsSiH with [l.l.l]propellane under photolytical decomposition of di-tert-butyl peroxide afforded products 17 and 18 in 1 3 ratio (Reaction 5.15) [36]. A rate constant of 6.0 x 10 M s at 19 °C for the addition EtsSi radical to [l.l.l]propellane was determined by laser flash photolysis [37]. Thus, it would appear that [l.l.l]propellane is slightly more reactive toward attack by EtsSi radicals than is styrene, and significantly more reactive than 1-hexene (cf. Table 5.1). 

Homolytic cleavage of most a bonds may be achieved if the compound is subjected to a sufficiently high temperature, typically about 200 °C. However, some weak bonds will undergo homolysis at temperatures little above room temperature. Bonds of peroxy and azo compounds fall in this category, and such compounds may be used to initiate a radical process. Di-tert-butyl peroxide, dibenzoyl peroxide... 

A formal reaction corresponding to equation 6 for the de-etherated parent species, 3-tcrt-butylperoxy-l,2-propandiol, is equation 13 for which the enthalpy of reaction is —308.2 kJmol. This value is about 29 kJmol less negative than the corresponding reaction for di-tert-butyl peroxide. 

A special reaction is the oxidation of l,2-di(carbazol-9-yl)ethane with air at 188°C in the presence of di-terr-butyl peroxide forming l,2-di(carbazol-9-yl)ethene. The same material was obtained from di-tert-butyl peroxide initiated decarbonylation of carbazol-9-ylethanal in the absence of air with air present, 9-methylcarbazole, dicarbazol-9-ylmethane, and polymer resulted." ... 

Typical procedure The mole ratio of alkene t-BuOOH catalyst was 10 10 0.25 and 40 mmol of the olefin serving as its own solvent. Thus, 10 mmol of TBHP (80% in di-tert-butyl peroxide) and 0.25 mmol of vanadium pentoxide were added to 50 mmol of the olefin and the reaction mixture was stirred at 60°C under a dinitrogen atmosphere. The products formed were analyzed by GC by comparison of their retention time with those of authentic samples. Good yields of epoxides were obtained only with an excess of olefin to TBHP of 5 1. That the olefin doubles up as the solvent makes for a more practical procedure. Typical results (34) are shown in Table 1 ... 

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