2.2- Dimethyl-1,3-propane diol

Dimethyl-l,3-propane Dinitrate (called Dimethyloldiethylmethane Dinitrate in CA), (CH3)2C(CH2-0N02)2 raw 194.15, N 14.43% It-yel liquid explosive was prepd by Spaeth. (Ref 2) by nitrating 2,2-dimethyl-l,3-propane-diol with mixed acid at 24-40°. It was claimed to be suitable for use with NC ... 

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. 

These admixtures are based on the 2.2-dimethyl-propane-1.3-diol (neo-pentyl glycol) of the formula (CH3)2C(CH20H)2, or similar chemical compounds. They are added in amount about 4 kg/m of concrete. 

The PTT is aromatic polyester prepared by the melt polycondensation of 1,3-propanediol (1,3-PDO) with either TPA or dimethyl terephthalate (DMT). The PTT is synthesized by the transesterification of propanediol with dimethylene terephthalate or by the esterification of propane diol with TPA. The reaction is carried out in the presence of hot catalyst like titanimn butoxide (Ti(OBu) ) and dibutyl tin oxide (DBTO) at a temperature of 260°C. The important by-products of this reaction include acrolien and allyl alcohol (Chuah, 2001). Direct esterification of propane diol and TPA is considered as the least economic and industrial method. The reaction is carried out in the presence of a heel imder a pressure of 70-150 kPa at a temperature of 260°C. The heel is usually referred to the added PTT oligomers which act as a reaction mediiun and increase the solubility of TPA (Chuah, 2001). Recent studies by different groups show that the selection of the catalyst plays a major role on the reaction rate and PTT properties. Commonly used catalysts like titanium (Doerr et al., 1994), tin (Kurian and Liang, 2001 Fritz et al., 1969) and antimony (Karayannidis et al., 2003 Fitz et al., 2000) compounds have their own limitations. Titanimn-based catalysts are active but the PTT is discolored, antimony-based catalysts are toxic and only active in polycondensation while tin-based compounds have lower catalytic activity. Karayannidis and co-workers (2003) reported the use of stannous oetoate ([CHj(CH2)3CH(C2Hj)COO]jSn) as the catalyst for PTT synthesis but its catalytic activity is poor, resulting in a low molecular weight PTT which was confirmed... 

It was found that the transesterification of dimethyl H-phosphonate with 1,2-propane-diol yields 4-methyl-2-hydro-2-oxo-l,3,2-dioxaphospholane [56]. Obviously, the first stage of the reaction furnished methyl-2-hydroxypropyl H-phosphonate. Subsequent intramolecular transesterification of the methyl-2-hydroxypropyl phosphonate yielded 4-methyl-2-hydro-2-oxo-l,3,2-dioxaphospholane. The specific reactivity of these esters of H-phosphonic acid is determined by the presence of a P-hydroxyl gronp. The role of the P-hydroxyl gronp may be regarded as an intramolecular catalysis. The reactivity enhancement of P-hydroxylethyl esters of H-phosphonic acid probably can be explained through hydrogen bonding, which favors the intramolecular transesterification reaction. 

An aq soln. of excess Ca-permanganate added dropwise with vigorous stirring at 0° to a soln. of 2,2-dimethyl-l,3-propanediol sulfite in glacial acetic acid-chloroform until the permanganate color persists 2,2-dimethyl-l,3-propane-diol sulfate. Y 71%.—The product could not be obtained directly from the diol. F. e. s. J. Lichtenberger and J. Hincky, Bl. 1961, 1495. 

A range of bis- and tris-spirocyclic cyclotriphosphazenes 182-187 containing bi-2-napthoxy, 2,2 -biphenoxy, 2,2-dimethyl-1,3-propane diamino, and 2,2-dimethyl-1,3-propane dioxy ligands have been prepared from the appropriate diamines and diols <2004POL979>. 

Hydroformylation of 2,6-dimethyl-6-hepten-2-ol produces hydroxycitronellal (equation 12).22 Subjecting allyl alcohol to hydroformylation reaction conditions with HCo(CO>4 yields only propanal, isomerization taking place more rapidly than hydroformylation.2 Phosphine-modified rhodium catalysts will convert allyl alcohol to butane-1,4-diol under mild conditions in the presence of excess phosphine, however (equation 13).5 30 31 When isomerization is blocked, hydroformylation proceeds normally (equation 14). An elegant synthesis of the Prelog-Djerassi lactone has been accomplished starting with the hydroformylation of an allylic alcohol (equation IS).32... 

When either an alcohol or an amine function is present in the alkene, the possibility for lactone or lactam formation exists. Cobalt or rhodium catalysts convert 2,2-dimethyl-3-buten-l-ol to 2,3,3-trimethyl- y-butyrolactone, with minor amounts of the 8-lactone being formed (equation 51).2 In this case, isomerization of the double bond is not possible. The reaction of allyl alcohols catalyzed by cobalt or rhodium is carried out under reaction conditions that are severe, so isomerization to propanal occurs rapidly. Running the reaction in acetonitrile provides a 60% yield of lactone, while a rhodium carbonyl catalyst in the presence of an amine gives butane-1,4-diol in 60-70% (equation 52).8 A mild method of converting allyl and homoallyl alcohols to lactones utilizes the palladium chloride/copper chloride catalyst system (Table 6).79,82 83... 

LIII) l-Guaiacyl-2-(dimethyl-pyrogallyl)-propane-l, 3-diol... 

Alkylene CCs have been prepared through the transesterification of appropriate glycols with dialkyl carbonates (usually diethyl or dimethyl carbonate) in the presence of a suitable catalyst. One of the first such examples was the synthesis of six-membered CCs by the transesterification of propane-1,3-diols with DEC catalyzed by sodium ethanolate (Equation 7.31) [289], The reaction was carried out at temperatures between 293 and 333 K, and a conversion yield of 40% was obtained. 

Dioxane is a colourless liquid, bp 105°C, readily soluble in all common solvents. It is prepared from formaldehyde and propane-1,3-diol in the presence of an acid catalyst. 2,2-Dimethyl-1,3-dioxane-4,6-dione 20 (Meldrum s acid) is obtained by cyclocondensation of acetone with malonic acid. Meldrum s acid represents a useful reagent in organic synthesis due to its reactivity as a malonate equivalent [131]. 

Adipic acid dimethyi adipate (polyesters), acrylamide (acrylonitrile co-polymers), acrylonitrile (acrylamide co-polymers), acrylic acid (acrylic polymers), buta-1,3-dlene (PS co-polymers, elastomers), butan-1,4-diol (polyesters), 2,2-bis(4-hydroxyphenyl)butan-1-ol (polyesters), 1,1-bis(4-hydroxyphenyl)cyclohexane (polyesters), 4,4 -(propane-2,2-diyl)-dlphenol known as bisphenol A (polyesters), ethyleneglycol (polyestere), formaldehyde (phenol-formaldehyde resins), isophthalic acid (PET), caprolactame and C -C,2 aminocar-boxyllc acids and their lactames (polyamides), melamine (amino-formaldehyde resins), methacryllc acid and methyl methacrylate (acrylic polymers), methylstyrene (PS and co-polymers), propyleneglycol (polyesters), sebacic acid and dimethyl sebacate (polyesters), styrene (PS and co-polymers), terephthalic acid and dimethyl terephthalate (PET), vinyl acetate (vinyl acetate co-polymers), vinyl chloride (PVC and co-polymers), vinylldenechlorlde (PVdC and co-polymers)... 

Components 1. CjHsOS, Dimethyl sulfoxide [67-68-5] 2. CjHgOj, Propane-1,2-diol [57-55-6] ... 

The formation of cyclic acetals and ketals from alkane diols other than ethylene glycol has been investigated in some detail [30, 30a, 30b]. It was found that with ketones ease of ketal formation is in the order 2,2-dimethylpropane-l,3-diol > ethylene glycol > propane-1, 3-diol, and that stability to acid is greatest with the resulting 5,5-dimethyl-l,3-dioxans. In the case of the diketone (1) it has been foimd that mono-ketalization at the 1-keto-group was more selective with... 

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