Dimethyl-l,3-propanediol

The flexibiHty of the final film is partiy controUed by the ratio of aromatic to aHphatic dibasic acids. The esters of highly substituted polyols such as neopentyl glycol (NPG) (2,2-dimethyl-l,3-propanediol) [126-30-7] 1,4-dimethylolcyclohexane (cyclohexanedimethanol (CHDM)) [27193-23-3] ... 

Aliphatic Glycidyl Ethers. Aliphatic epoxy resins have been synthesized by glycidylation of difunctional or polyfunctional polyols such as a 1,4-butanediol, 2,2-dimethyl-l,3-propanediol (neopentyl glycol), polypropylene glycols, glycerol, trimethylolpropane, and pentaerythritol. 

Due to the differences in the values relative to any one system, conclusions cannot easily be drawn from the activation parameters listed in Table 3. However, an analysis of the results relative to 1,2-ethanediol, 2,2-dimethyl-l,3-propanediol, 1,5-pentanediol, 1,10-decanediol and diethylene glycol shows that a slight difference can be observed between aromatic and aliphatic acids the activations enthalpies and entropies are in the ranges 70, 100 kJ mol"1 and -SO, -130 J K"1 mol-1 for aromatic acids, and in the ranges 50, 70 kJ mol"1 and -200, -100 J K"1 mol-1 for the aliphatic acids. 

Several authors studied the influence of substituents on activation parameters. Bad-dar et al.315 who studied the polyesterification of y-arylitaconic anhydrides and adds with 1,2-ethanediol found that in the non-catalyzed reaction a p-methoxy substituent decreases both the activation enthalpy and the entropy whereas an increase is observed with a p-chloro substituent. On the other hand, Huang et al., who studied the esterification of 2,2-dimethyl-l,3-propanediol with benzoic, butanedioic, hexanedioic, decanedioic and o-phthalic add found the same values since the activation enthalpy is 64 kJ mol-1 for the first reaction and 61 kJ mol-1 for the others. 

Dihydroxy dime thylethylme thane or 2,2-Dimethyl-l,3-propanediol, (CHa)2C(CH2OH) 2 (Ref 1). Its dinitrate ... 

Di(methylol) propane Dinitrate 2,2-Di(nitroxymethyl)-propane Pentaglycol Dinitrate 2,2-Dimethyl-l, 3-propanediol Dinitrate or D i meth y I ol dimethyl me thane Di nitrate, abbreviated as PGcDN,... 

Neopentyl glycol, or 2,2-dimethyl-l,3-propanediol [126-30-7] (1) is a white crystalline solid at room temperature, soluble in water, alcohols, ethers, ketones, and toluene but relatively insoluble in alkanes (1). Two primary hydroxyl groups are provided by the 1,3-diol structure, making this glycol highly reactive as a chemical intermediate. The gem-dimethyl configuration is responsible for the exceptional hydrolytic, thermal, and uv stability of neopentyl glycol derivatives. 

For convenience, the letters T (terephthalic acid), I (isophthalic acid), H [50/50 cw/trarw-hexahydroterephthalic acid (1,4-cyclohexane-dicarboxylic acid)], and NPG [neopentyl glycol (2,2-dimethyl-l,3- propanediol)] are used to refer to the polyesters prepared from these intermediates thus, T50I(NPG) is the copolyester from neopentyl glycol and equimolar amounts (50/50 molar ratio) of terephthalic and isophthalic acids. 

Benzyloxyisothiazole 316 (R = H) is regioselectively lithiated at C-5 with LDA and the lithiated species reacts with MeOD and various C-electrophiles <2002JOC2375>. Treatment with I2 or B(0/-Pr)3/2,2-dimethyl-l,3-propanediol affords the iodo compound 316 (R = I) and the boronic ester 315, respectively (see Section 4.05.7.7) <2004JOC1401 4he Grignard reagent of 3 iodoisothiazole reacts rvith a series of electrophiles 1995SC1383. ... 

Dimethyl-l,3-propanediol (neopentyl glycol) [126-30-7] M 104.2, m 128.4-129.4 , b 208 /760mm. Crystd from benzene or acetone/water (1 1). 

The ditosylate ester of 2,2-dimethyl-l, 3-propanediol also did not decompose when used to form the peraza macrocycles under mild conditions (Krakowiak,... 

Transformation of 2,2 -dimethyl-l,3-propanediol yielded the corresponding diamine (70%) and the intermediate amino alcohol (7%) with 75% conversion (Figure 2). Temperatures above 210 °C were detrimental to diamine selectivity because of /5 o-butylamine formation by re/ro-aldol or retro-formylation reactions (Scheme 7). In the other two substrates, whieh have an H atom in C2 position, direct elimination of water to form a reactive allylic alcohol (or a,j0-unsaturated ketone or amine) was the major side-reaction which reduced selectivity. 

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