Of 1,2-butanediol

Fig. 9 Stereoselective oxidation of 1,2-butanediol to (S)-1,2-butanediol catalyzed by glycerol dehydrogenase with simultaneous cofactor regeneration using the system 2-ketoglutarate/gluta-mate dehydrogenase (GluDH)...

However, apart from the fact that the polyaddition of oxygen takes place not only at 1.4- but also at 1,2s causing die co-production of 1,2-butanediol, the hydrogenolysis step does not allow economically interesting diol yields. 

The reductive elimination of the cyclic sulfate of 1,2-butanediol led to tmns-2-butene selectively. Aromatic vicinal dioxalates underwent fragmentation and elimination on cathodic reduction to give alkenes. Mexo-(Et02COCH(QH5))2 gave 80% trans-stilbene [365]. 

Using the peroxyacid epoxidation of an alkene and the ring opening of an epoxide, devise a two-step synthesis of 1,2-butanediol from 1-butene. 

Etylene glycol/adipic acid and 1,4-butanediol/succinic acid were copolymerized in the presence of 1,2-butanediol and 1,2-decanediol to produce etl rl and n-octyl branched poly(ethylene adipate) (PEA) and poly(butylene succinate) (PBS), respectivefy [77]. The modified Strum test showed that the two polymers were assimilated to CO2 at a similar rate. As the degree of chain branching increased, the biodegradation rate of PEA increased to a greater extent than that of PBS due to the faster reduction in the crystallinity of PEA compared to the crystallinity of PBS. 

Baker et al. (2004a) discussed formation of hydroxycarbonyls from alkanediols for example, l-hydroxy-2-butanone is formed in the oxidation of 1,2-butanediol. 

The reaction of butyllithium with 1-naphthaldehyde cyclohexylimine in the presence of (/C )-l,2-diphenylethane-1,2-diol dimethyl ether in toluene at —78 °C, followed by treatment with acetate buffer, gave 2-butyl-1,2-dihydronaphthalene-l-carbaldehyde, which was then reduced with sodium borohydride in methanol to afford (1 R,2.S)-2-butyl-1 -hydroxymcthyl-1,2-dihydronaphthalene in 80% overall yield with 91 % ee83. Similarly, the enantioselective conjugate addition of organolithium reagents to several a,/J-unsaturated aldimines took place in the presence of C2-symmetric chiral diethers, such as (/, / )-1,2-butanediol dimethyl ether and (/, / )- ,2-diphenylethane-1,2-diol dimethyl ether. 

Figure 8. Typical adsorption potential shifts as a function of adsorbate surface concentration. (1) At the free surface of a solution (real behavior), (2) ideal behavior, and (3) at a metal (Hg)/solution interface. Experimental points for adsorption of 1,4-butanediol from Ref. 328.

Significant synthetic applications of the nickel-salen catalysts are the formation of cycloalkanes by reduction of <>, -a-dihaloalkanes255,256 and unsaturated halides,257,258 the conversion of benzal chloride (C6H5CHC12) into a variety of dimeric products 259 the synthesis of 1,4-butanediol from 2-bromo- and 2-iodoethanol260 or the reduction of acylhalides to aldehydes261 and carboxylic acids.262... 

An example of the use of 1,4-butanediol diglycidyl ether for the activation of soluble dex-tran polymers is given in Chapter 25, Section 2.3. One end of the fezs-epoxide reacts with the hydroxylic sugar residues of dextran to form ether linkages, which terminate in epoxy functionalities. The epoxides of the activated derivative then can be used to couple additional mol-ecules-containing nucleophilic groups to the dextran backbone. 

The most important reaction is the oxidative addition of two moles of acetic acid to butadiene to form 1,4-diacetoxy-2-butene (21) with the reduction of Pd2+ to Pd°. In this reaction, 3,4-diacetoxy-l-butene (127) is also formed. In order to carry out the reaction catalytic with regard to Pd2+, a redox system is used. This reaction attracts attention from the standpoint of industrial production of 1,4-butanediol. For this purpose, the formation of 127 should be minimized. Numerous patent applications have been made (examples 113-115), but no paper treating the systematic studies on the reaction has been published. 

Candida parapsilosis was found to be able to convert (k)-1,2-butanediol to (S)-l,2-butanediol through stereospecific oxidation and asymmetric reduction reactions [72]. The oxidation of (k)-1,2-butanediol to l-hydroxy-2-butanone and the reduction of l-hydroxy-2-butanone to (S)-l,2-butanediol were cataly-... 

Fig. 7. Time course of repeated resolution. The repeated resolution of 1 vol.% 1,2-butanediol was carried out in the presence of 1 mmol NAD+ ( ) or phenazinemethosulfate (o), or in the absence of an electron acceptor ( ) under aerobic conditions...

Oligoester Reaction product of 1,4-butanediol diglycidyl ether, 2-ethyl-1, 3-hexanediol, and 4-methy1-1,2-cyclohexane dicarboxylic acid anhydride MW 830 f = 4 r - 0.75. 

In many cases almost quantitative yields are reported for the formation of v/c-dinitrate esters from the reaction of simple alkyl and dialkyl epoxides with dinitrogen pentoxide (Table 3.2). Some of the products formed include ethylene glycol dinitrate (2) (96%), 1,2-propanediol dinitrate (8) (96 %), 2,3-butanediol dinitrate (94 %) and 1,2-butanediol dinitrate (96 %). Reaction times are of the order of 5-15 minutes. 

The hydrolysis of these model precursors was studied at 37 , with catalysis by hog liver esterase. The major product, isolated in 60-70% yield from the hydrolysis of a-acetoxyNPy, was 2-hyd oxy-tetrahydrofuran. This compound was identified by comparison to a reference sample,prepared by lead tetraacetate oxidation of 1,2,5-pentanetriol (53). Additional evidence was obtained by lithium aluminum hydride reduction of the product to 1,4-butanediol. Minor amounts of butenals were also identified as products of the hydrolysis of a-acetoxy IPy. 

Add 6.3 g (0.0310 mol) of isophthaloyl chloride and 2.8 g (0.0311 mol) of 1,4-butanediol (1% excess) to a 50-ml ampule used for polymerization equipped with a capillary tube for a nitrogen inlet extending below the surface of the reaction mixture. 

In contrast, hydrogenation of 1,2-diketones that proceeds via 2-hydroxy ketones exhibits marked syn or meso selectivity (Scheme 60), although the enantiomeric preference follows the general sense given in Scheme 47 (92). Thus, (i )-BINAP-Ru-aided hydrogenation of diacetyl gives a 26 74 mixture of enantiomerically pure (R,R)-2,3-butanediol and the meso diol. 

Patients with propionic or methylmalonic acidemia also secrete 2,3-butanediols (d-,l- or meso) and usually also 1,2-propandiol in their urine. Secretion of 1,2-propanediol is also observed during... 

Dissolve 14 mg of NaBFL in 7 mL of lMNaOH. Add this solution along with 7 mL of 1,4-butanediol-diglycidylether to the washed agarose, with mixing. Allow the reaction to proceed for 10 h or more at room temperature with gentle stirring. 

Exercise 16-41 Predict the products to be expected from acid-catalyzed rearrangements of 1,2-propanediol and 2-methyl-2,3-butanediol. 

The incubation digest (7.0 ml) contained 1 ml of 0.022 M phenyl phosphate 2.5 ml of 0.1 M acetate buffer, pH 5.0 0.5 ml of test enzyme solution and 3.0 ml of solutions of acceptors giving a final concentration as shown in the third column. Incubation time, 30 min. Digests were inactivated by 3.0 ml of 10% trichloroacetic acid solution and were analyzed for phenol and inorganic phosphate. In the case of the standard acceptor, 1,4-butanediol, the expected transfer product, 1,4-butanediol phosphate, was isolated in a yield of 35% from a large-scale experiment. The hydrolysis of this phosphate ester by prostatic acid phosphatase liberated approximately equimolar amounts of 1,4-butanediol and inorganic phosphate. 

Terpolymerization of MM A and 1,2-Butanediol Dimethacrylate with l, 3 and 6 The terpolymerization of MMA and 1,4-butanediol Dimethacrylate (BDDM) with azo monomers leads to networks with labile, azo groups as network bridges 50,51 These polymerizations were carried out in emulsion using dimyristile peroxydicarbon-ate as the initiator (see Table 3.12). 

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