Penta erythritol

We have noted above (Sect. 8.3) that certain substituted benzoic acids have been used in the synthesis of endolipophilic cryptands but it is the glycerol and penta-erythritol units which have been used most commonly in this application. These are discussed separately, below. 

Coxon and Stoddart have directed their attention to the formation of penta-erythritol-derived cryptands. With these molecules, the strategy was to block one pair of hydroxyl groups as an acetal and form a crown from the remaining diol. In the first of the two reports cited above, this was accomplished by treating the 0-benzylidine derivative of pentaerythritol with base and diethylene glycol ditosylate. The crown was then treated with a mixture of UAIH4 and BF3 which gives partial reduction of the acetal as shown in (8.9), above. The monoprotected diol could now be treated in a fashion similar to that previously described and the benzyloxy cryptand (77) would result. The scheme is illustrated below as Eq. (8.10). 

PNDA = p-dinitroso diphenyl amine PETA-penta erythritol triacrylate DHBP-peroxy hexane values in parentheses are after aging at 100°C, 72 h. 

An examination has, therefore, been made of the effect of solutions of potassium chloride on the electrolytic resistance of films cast from a penta-erythritol alkyd, a phenolformaldehyde tung oil and an epoxypolyamide varnishPotassium chloride was chosen because its conductivity is well known and unpigmented films were first examined in order to eliminate the complexities of polymer/pigment interaction. 

Fig. 14.2 Relationship between the logarithm of the resistance of D and / Aims of a penta-erythritol alkyd paint, containing 6-1% iron oxide by volume, and the concentration of the potassium chloride solutions in which they were immersed (courtesy Bril. Polym. J., 3, 41...

Aubertein Rehling (Ref 15) have shown that treatment with water at approx 100° causes PETN to hydrolyze. At 125° and under pressure, hydrolysis proceeds quite quickly, and is considerably enhanced by the presence of 0.1% HNO3. Regardless of whether it occurs in water alone or in water acidified with nitric acid, the hydrolysis produces mainly Penta-erythritol Dinitrate. A dil NaOH soln causes PETN to hydrolyze.more rapidly than acidified water. PETN neither reduces Fehling s reagent nor enters into addition products with any aromatic nitro compd. In this respect it differs from both Erythritol Tetranitrate and Nitro-mannitol... 

Penta-erythritol Diacetate Dipropionate", ERDE 11/M/58 (Oct 1958), AD 206266 (DDCSTI users only) 6) V. Pasquale, Feasibility Study on Using Low Acetyl Cellulose Acetate Inhibitor for Production Cast Grains , NOSIH TR 317 (10 July 1970), AD 510578 (Conf) 7) CPIA Solid Propellant Manual , CPIA/M2 (28 Jan 1974), unit 1069 (Conf)... 

More recently Frechet and Gitsov [130] used a similar approach as above and synthesized a novel series of dendritic copolymers derived from a central penta-erythritol core unit. These hybrid star molecules behaved as unimolecular micelles with different core-shell conformational-structures as a response to the polarity of the solvent used. 

Severin and coworkers reported (146) the reaction of tris(2-aminoethyl)amine and 4-formylphenylboronic acid with penta-erythritol to give, via multicomponent assembly, the boronic acid based macrobicyclic cage 35 (Fig. 25). The cage has the form of an ellipsoid with a diameter of 20.5 A and binds two Cud) ions in a fashion similar to the smaller tren-based cryptands. The reversible formation of boronic esters has also been employed to build other hollow structures such as nanotubes (147) and porous covalent organic frameworks (148,149). 

Bioabsorbable star polymers consisting of p-dioxanone, glycolide, and penta-erythritol were prepared by Bennett et al. (3) and used as surgical adhesives and as bone putty. 

Fig. 144. Above urea (c projection). 310 and 310 planes have the same structure amplitude. Below penta-erythritol (c projection). 310 and 3l0 planes have different structure amplitudes. Note positions of atoms with respect to planes in each case.

The nature of the relation which exists between the symmetry of diffraction effects and that of the crystal may be gathered by consideration of the hkO intensities of two simple tetragonal crystals—urea (0---C(NH2)2), whose point-group symmetry is 42m, and penta-erythritol (C(CH2OH)4), belonging to class 4. For urea (see Fig. 144), the intensity of 310 is the same as that of 310, as is obvious from the relation of the molecules to the traces of these planes the equality... 

Laue photographs of ammonium chloride (above) and penta-erythritol (below). X-ray beam along fourfold axis... 

A nitrator filled with 300 kg of 93-95% nitric acid is fed with 60 kg pentaery-thritol previously dried at 100°C. By means of a cooling jacket a temperature of 20°C is maintained in the nitrator. The equipment is constructed of aluminium, and fitted with a stirrer operating at 120 r.p.m., with a funnel for adding the penta-erythritol and with an outlet for discharging the product at the bottom. 

The Cannizzaro ruction with benzaldehyde is described in a number of manuals of organic laboratory practice. The preparation of penta-erythritol (p. 101) and the conversion of furfural into furfuryl alcohol and furoic acid are described in Organic Syntheses.83 Below are a few typical examples of the reaction covering a number of the modifications discussed in the foregoing pages. 

Standard synthetic methods are used to couple partially protected penta-erythritol to the core cell and subsequent dendrimer surfaces [82, 133]. Synthesis of the first generation involves displacement of bromide from C(CH2Br)4 with a masked pentaerythritol (bicyclic orthoester). One obtains three hydroxyl groups per terminal group after deprotection (Scheme 24). Therefore, a series that triples both its surface hydroxyl groups and its molar mass is obtained (see Table 5). 

Matter patented detonators made by using penta-erythritol tetranitrate in conjunction with a detonating substance. 

Funk [3] prepared hydrogels with different pH values by reacting 90 parts of hydrophilic polymeric agents with glacial acrylic acid, water, and penta-erythritol triallyl with 10 parts of acrylic acid, sorbitan monococoate, and allyl methacrylate. 

The same MEKC system was also used for the separation of a test mixture of 15 compounds of interest in high explosive analysis, including nitroguanidine, ethylene glycol dinitrate, diethylene glycol dinitrate, l,3,5-trinitro-l,3,5-triazacyclohexane (RDX), nitroglycerin, 2,4,6-trinitrotoluene (TNT), penta-erythritol tetranitrate, and picric acid, with excellent resolution except for the overlapping of 1,5- and 1,8-isomers of dinitronaphthalene. Also, separation of all the components (26) of the two sets of standards was attempted with extremely limited coelutions. 

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