2, 4-Di -9-isopropyl

Some small amount of byproduct formation occurs. The principal byproduct is di-isopropyl ether. The reactor product is cooled, and a phase separation of the resulting vapor-liquid mixture produces a vapor containing predominantly propylene and propane and a liquid containing predominantly the other components. Unreacted propylene is recycled to the reactor, and a purge prevents the buildup of propane. The first distillation in Fig. 10.3a (column Cl) removes... 

The following preparation of triethyl phosphite illustrates the interaction of phosphorus trichloride and ethanol in the presence of dimethylaniline the preparation of di-isopropyl hydrogen phosphite illustrates that of phosphorus trichloride and isopropanol in the absence of a tertiary amine. 

Meanwhile set up the ether distillation apparatus as used in the preparation of triethyl phosphite (p. 308). Distil off the ether and then fractionally distil the residue at water-pump pressure. The di-isopropyl hydrogen phosphite distils at 79Vi4 mm. other b.ps. are 8o°/i5 mm., 82-5°/i7 mm. Yield, 25 g., 89%. 

Di-isopropyl hydrogen phosphite is a colourless mobile liquid, which, unlike triethyl and tri-isopropyl phosphite, is completely miscible with water, due undoubtedly to the polar P=0 group. 

B) The following simpler preparation of di-isopropyl hydrogen phosphite using the same quantities of reactants requires no solvent or ammonia, but gives a lower yield. 

Ethers. Diethyl ether, di-n-propyl ether, di-isopropyl ether, ani ... 

ISOPROPYL ETHER see DI-ISOPROPYL ETHER ISOPROPYL FORMATE 2408 625-55-8... 

ISOPROPYL PEROXYDICARBONATE see DI-ISOPROPYL PEROXY-ISOPROPYL PROPIONATE 2409 637-78-5... 

Apparently a substantial spacer is also allowable between I he aromatic ring and the carboxy group. Gemfibrozi 1 (52), a iiypotriglyceridemic agent which decreases the influx of steroid into the liver, is a cl ofibrate homologue. It is made readily liy lithium di isopropyl amide-promoted alkylation of sodium iso-propionate with alkyl bromide 51. 

A series of pyrrolidones shows promise of being cognitionenhancing agents. One of these, amacetam 3), is synthesized readily by ester-amide exchange between ethyl 2-oxo-l-pyrroli-dineacetate U) and ]1, -di isopropyl ethyl enedi amine ( ). ... 

Oxygen was added as oxygenated hydrocarbon components methyl tert-butyl ether (MTBE), tert-amyl methyl ether (TAME), ethyl tert-butyl ether (ETBE), di-isopropyl ether (DIPE), ethanol, methanol, and tertiary butyl alcohol (TBA). The properties of oxygenates, as they relate to gasoline blending, are shown in Table 10-1. 

In the case of allyl peroxides (12 X= CH2, A=CH2, BO),1 1 1 intramolecular homolytic substitution on the 0-0 bond gives an epoxy end group as shown in Scheme 6.18 (1,3-Sn/ mechanism). The peroxides 52-59 are thermally stable under the conditions used to determine their chain transfer activity (Table 6.10). The transfer constants are more than two orders of magnitude higher than those for dialkyi peroxides such as di-f-butyl peroxide (Q=0.00023-0.0013) or di-isopropyl peroxide (C =0.0003) which are believed to give chain transfer by direct attack on the 0-0 bond.49 This is circumstantial evidence in favor of the addition-fragmentation mechanism. 

In the course of this study, the authors determined /Lvalues for dibenzyl, methyl phenyl, methyl p-nitrophenyl, di-p-tolyl, di-isopropyl and tetramethylene sulphoxides and for diethyl, dipropyl and dibutyl sulphites. The /Lscales are applied to the various reactions or the spectral measurements. The /Lscales have been divided into either family-dependent (FD) types, which means two or more compounds can share the same /Lscale, family-independent (FI) types. Consequently, a variety of /Lscales are now available for various families of the bases, including 29 aldehydes and ketones, 17 carboxylic amides and ureas, 14 carboxylic acids esters, 4 acyl halides, 5 nitriles, 10 ethers, 16 phosphine oxides, 12 sulphinyl compounds, 15 pyridines and pyrimidines, 16 sp3 hybridized amines and 10 alcohols. The enthalpies of formation of the hydrogen bond of 4-fluorophenol with both sulphoxides and phosphine oxides and related derivatives fit the empirical equation 18, where the standard deviation is y = 0.983. Several averaged scales are shown in Table 1588. 

Other alkyl sulfones studied are di-isopropyl, methyl isopropyl and di-t-butyl sulfones. 

Recently, Naskar et al. have used a fourth method, i.e., use of a novel cross-linking agent, bis(di-isopropyl) thio-phosphoryl disulfide, which reacts with both rubbers, thereby linking the two phases intimately and providing a robust blend [29]. The reaction scheme is given in Figure 11.7. 

Peggion E, Cosani A, Mattucci AM, Scoffone E (1964) Polymerization of gamma-ethyl-L-glutamate-N-carboxyanhydride initiated by Di-N-butyl and Di-isopropyl amine. Biopolymers 2 69-78... 

A few results have been reported on the oxidation of cyclohexanol by acidic permanganate In the absence of added fluoride ions the reaction is first-order in both alcohol and oxidant , the apparent first-order rate coefficient (for excess alcohol) at 25 °C following an acidity dependence k = 3.5-1-16.0 [H30 ]sec fcg/A , depends on acidity (3.2 in dilute acid, 2.4 in 1 M acid) and D2o/ H20 is f-74. Addition of fluoride permitted observation of the reaction for longer periods (before precipitation) and under these conditions methanol is attacked at about the same rates as di-isopropyl ether, although dioxan is oxidised over twenty times more slowly. The lack of specificity and the isotope effect indicates that a hydride-ion abstraction mechanism operates under these conditions. (The reactivity of di-isopropyl ether towards two-equivalent oxidants is illustrated by its reaction with Hg(II).) Similar results were obtained with buffered permanganate. 

Two studies have been performed by Littler on the oxidation of cyclohexanol by Hg(II), the second leading to more detailed and reliable data. The reaction is first-order in both oxidant and substrate but the rate is independent of acidity. E is 24.8 kcal.mole AS is 1 eu, Ath/Acd is 3.0 and ko ol HzO 1-30-At 50 °C di-isopropyl ether is attacked at about one-half the rate of isopropanol, which implies that hydride ion abstraction is occurring in both cases. This is supported in the case of cyclohexanol by the isotope effects. 

The ready oxidation of di-isopropyl ether by Hg(II) perchlorate " is a good indication that this oxidant can function as a hydride-ion acceptor, viz. 

The remarkable inertness of dialkyl ethers to one-equivalent oxidants is good evidence that the readier oxidation of alcohols involves more than simple electron abstraction. Di-isopropyl ether is oxidised by Co(III) in CH3CN-H2O mixtures with complicated kinetics individual runs show first-order decay of Co(III) but the rate coefficients increase with increasing [Co(III)], and the order with respect to substrate is less than one but is neither fractional nor of a Michaelis-Menten type. The main product is acetone and the following reaction sequence is proposed... 

A number of other types of chiral auxiliaries have been employed in enolate alkylation. Excellent results are obtained using amides of pseudoephedrine. Alkylation occurs anti to the a-oxybenzyl group.93 The reactions involve the Z-enolate and there is likely bridging between the two lithium cations, perhaps by di-(isopropyl)amine.94... 

In the area of process monitoring TLC has been used for the study of the thermal decomposition of zinc di-isopropyl dithiophosphate (antiwear additive in lubricating oils) [458]. TLC analysis has been reported as a quality control tool for analysis of dispersing agents (alkylsalicylates, thioalkylphenolates), AOs (dithiophosphates, dialkyldithiophosphates) and their intermediates in lubricating oil (UV detection,... 

Figure 12.33 Separation of isopropyl alcohol (IPA) and water mixture using di-isopropyl ether (DIPE) as entrainer in heterogeneous azeotropic distillation.

---