Analogous hydrolysis

The submitters report that /3-methylglutaraldehyde may be isolated at this point from an analogous hydrolysis. The hydrolysis is carried out with 196 g. of 3,4-dihydro-2-methoxy-... 

Nevertheless the results quoted above for the breakdown of dimethyl hemiorthobenzoate indicate that (kinetic) general acid catalysis should be detectable in the methanolysis of methyl benzoate (Bransted a = 0.49) and probably in the analogous hydrolysis of methyl benzoate. Therefore any mechanism proposed for these reactions must be able to account for this. 

Then, pseudo-p-DL-gulopyranose (14) was synthesized by hydroxylation of 2,5-di-hydroxy-3-cyclohexene-l-methanol triacetate (12), which was prepared by Diels-Alder cycloaddition of 1,4-diacetoxy- 1,3-butadiene (10) and allyl acetate (11), with osmium tetroxide and hydrogen peroxide and successive acetylation as the pentaacetate (13). Analogous hydrolysis of 13 in ethanolic hydrochloric acid afforded the free pseudosugar 14 in 33% yield from 12 [2] (Scheme 7). 

The submitters report that /3-methylglutaraldehyde may be isolated at this point from an analogous hydrolysis. The hydrolysis is carried out with 196 g. of 3,4-dihydro-2-methoxy-4-methyl-2H-pyran in 650 ml. of water and 15 ml. of concentrated hydrochloric acid for 3 hours. After neutralization with sodium bicarbonate, the solution is saturated with sodium chloride and extracted continuously with ether for 20 hours. The ether is removed by distillation, and the product is dried thoroughly by azeotropic distillation using a benzene-hexane mixture. Distillation affords /3-methylglutaraldehyde, b.p. 85-86°/15 mm., 1.4307-1.4351. Yields up to 90% have been secured. The aldehyde polymerizes on standing but is stable as a 50% solution in water or ether. The monomer may be recovered by careful destructive distillation of the polymer. 

Amino-7-methyl- and -8-methyl-2-methylsulfonyl-8-azapurine, refluxed (2 h) in methanolic sodium methoxide, gave the 2-methoxy analogs (80% yields). 8-Methyl-2-methylsulfonyl-8-azapurin-6-one, refluxed with ethanolic sodium ethoxide, furnished 89% of the 2-ethoxy analog. Hydrolysis of the 2-methylsulfonyl group to a 2-oxo function in similar compounds was effected by stirring for 1 day at room temperature with N potassium hydroxide. Exceptionally, 7-methyl-2-methylsulfonyl-8-aza-purin-6-one underwent further hydrolysis to l-methyl-4-ureido-l,2,3-tria-zole-5-carboxylic acid (27). ... 

Dimethyl-phenoxy-phosphonylmethyl) -benzoic add N,N -diethyl(4-vinylphenyl)amidine EDMA THE Using transition state analog hydrolysis of 4-(3,5-dimethyl-phen-oxycar bony lmethyl)-benzoic acid to 4-carboxymethyl-benzoic acid and 3,5-dimethyl-phenol in MeCN/buffer [176]... 

In the presence of excess SCN , the decomposition of HOSCN and (SCN)2 around pH 4.0 in acetate buffer and the decomposition of OSCN around pH 7.0 in phosphate buffer have been recently investigated in detail, and it was shown that the observed mechanisms are relevant to the stability of OSCN at physiological pH (unpublished results). As SCN is considered to be a pseudohalide in several aspects of reactivity (32-34), some of the interpretation was based upon analogous hydrolysis chemistry of the halogens (88,107,108). The proposed mechanism of decomposition of HOSCN/OSCN is illustrated in Eqs. (26)-(35) ... 

Polysulfone is thermo-mechanical and chemically durable thermoplast. But in solution, which is catalyzed by alkali, it becomes sensitive to nucleoph-ylic replacements. In polar aprotone dissolvents at temperatures above 150 °C in the presence of spirit solution of K COj it decomposes into the bisphenol A and diarylsulfonic simple esters. The analogous hydrolysis in watery solution of K2CO3 goes until phenol products of decomposition. This reaction is of preparative interest for the synthesis of segmented block-copolyester simple polyester - polysulfone. The transetherification of polysulfone, being... 

The series of complexes of unestablished structure, but containing presumably 7C-bonded ligands has been prepared by the cryochemical method.The interaction of 2,4-dimethylbutadiene-l,3 with lanthanoid atoms (La,Er) under conditions of cocondensation at 77 K leads to a brown solid product [25]. The product may be divided into three fractions by the successive extraction in pentane, toluene and THF. The elemental composition of the main fraction (soluble in THF) corresponds to the formula (Me2C4H4)2Ln. Butadiene-1,3 gives products of the composition (C4H )3Ln (Ln = Nd, Sm, Er) under the same conditions. Butene-2 or 2,3-dimethylbutene-2 is the main volatile product of the (R2C4H4)2Ln (R = H, Me) hydrolysis. Analogous hydrolysis products have been observed for complexes with other unsaturated ligands [26]. 

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