Propan-1,2-diol, reaction with

Urea (118 g, 1.96 mols) was added to 192 g (0.98 mol) of 3-(3, 5 -dlmethylphenoxy)-1,2-propane-diol which had previously been heated to 150°C. The reaction mixture was then heated rapidly to 195° to 200°C and maintained at this temperature for 5 hours with constant stirring. The resulting mixture was partitioned between water and ethyl acetate and the ethyl acetate layer was dried over sodium sulfate and concentrated. The residue was distilled in vacuo and the fraction boiling at 220° to 225°C/1.5 mm was collected. Yield, 172 g (79%). The distillate was crystallized from dry ethyl acetate MP, 121.5° to 123°C. 

In contrast to NjPjCle, N4P4Q8 is extremely reactive towards difunctional reagents. This has led to the isolation of several decomposition products. Reactions with Af-methyl ethanolamine [87], 1,3-propane diol and 1,3-diamino propane afford mainly spiro products [138]. A detailed investigation on the reactions of N4P4CI8 with HO- CH2) -OH (n = 3, 4) has revealed that... 

Porous affinity membranes based on hydrolyzed poly(GMA-co-EDMA) grafted with glicidyl methacrylates oligomers were also reported [2,60]. Tennikova et al. [2] prepared functionalized macroporous poly(GMA-co-EDMA) membranes by reaction with propane sulfone, diethylamine, or water, leading to the formation of corresponding sulfonic acid, diethylamino or diol-derivatized stationary chromatographic phases. Unfortunately, the poly(GMA-co-EDMA) membranes are mechanically weak and due to their hydrophobic character may cause nonspecific adsorption of proteins. 

Phosgene reacts, sometimes violently, with a large number of common inorganic (Chapter 9) and organic (Chapter 10) substances. Hazardous reactions with lithium, sodium, potassium, aluminium, lithium amide, hexa-2,4-diyn-l, 6-diol, propan-2-ol, and hexafluoropropene have been mentioned specifically [1787]. Mixtures of potassium and phosgene are reported to explode when subjected to shock [1913a]. In addition, phosgene... 

The parameter K can also, like values in enzyme kinetics, be an agglomeration of rate constants that refers to a steady state, rather than an equilibrium situation. Rapid reaction kinetics, in the case of propane-1,2-diol, established that the intermediate was kinetically competent.The reaction with pinacol, where K is very large and the reaction is cleanly second order over a wide range of pinacol concentration,exhibited general acid and general... 

The point has recently been made that the kinetic data which indicate that the cyclic intermediates are involved are also compatible with mechanisms in which the true reaction is a bimolecular one and the complexes of reactants are inert. In support of this reinterpretation is the observation of an induction period in the reaction with propane-1,2-diol. Although the point is valid, there are two reasons why the Bunton mechanism of Figure 6.65 should be maintained. The first is the rapid-reaction work, which clearly showed the kinetic competence of an absorbing complex. The second is Occam s razor, which would reject the parasitic equilibria plus unspecified bimolecular process in favour of the simpler Bunton proposals. 

A series of alkyl, alkoxy or acylamino 1,3-proanediol derivatives substituted in 2-position have been subjected to lipase-catalyzed acylation, and the monoacetates (1-12, 19, 20, 23-38, 40-42) were obtained with moderate to high enantiomeric excess (Table 11.1-17). For the monoacetates 1-12, reactions with and in ethyl acetate are usually slower than those with and in vinyl acetate. As in the hydrolysis of the corresponding diacetates, much higher selectivities were recorded with the yet unidentified carboxyl esterase from crude pig pancreas lipase. An excellent lipase for the enantioselective acylation of 3-benzyloxy-l,3-propane diol is Pseudomonas fluor-escens lipase, which gives high selectivity with vinyl acetate, isopropenyl acetate and ethyl acetate. By carrying the acylation further, to a certain extent to the diacetate, the enantiomerically pure monoacetate should be obtainable. 

PROPANEDIOL or PROPANE-1,3-DIOL (504-63-2) C3H8O2 Combustible liquid (flash point 174°F/79°C cc Fire Rating 2). Violent reaction with strong oxidizers, alkalis. Incompatible with sulfuric acid, nitric acid, caustic materials, aliphatic amines, isocyanates, boranes. On small fires, use dry chemical powder (such as Purple-K-Powder), alcohol-resistant foam, or CO2 extinguishers. 

In a recent study (120), measurements were made of the molar cyclization equilibrium constants Kx for cyclics (0(CH2)i00C0(CH2)4C0)x with x = 1—5 in an undiluted equilibrate of poly(decamethylene adipate) (PDA) at 423 K, and for cyclics (0(CH2)30C0(CH2 )2 CO)x with x = 1-7 in an undiluted equilibrate of poly(trimethylene succinate) (PTS) at the same temperature. The polymers were prepared from dimethyl adipate and decamethylene glycol and from dimethyl succinate and 1,3-propane diol using tetraisopropyltitanate and equilibrated at the required temperature in four-necked glass reaction kettles. Cyclics were extracted from the polymeric equilibrates and analysed by g.p.c. by methods described in Ref. (120). Individual cyclics were also prepared from the polyesters by the general pyrolytic method of Carothers and these were used for identification and calibration purposes. 

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