Heptanol, formate

SYNS FORMIC ACID, HEPTYL ESTER HEPTANOL, FORMATE n-HEPTYL METHANOATE... 

The structures of anionic, triple-nuclear osmium and iron cluster catalysts supported on copolymers of styrene and divinylbenzene were analyzed by means of IR spectroscopy. Their catalytic activity during 1-hexene hydroformylation [250] and C5H5NO2 carbonylation [251] were investigated. It was found that isomerization proceeds simultaneously in the presence conventional catalysts. In the absence of moisture, a triple-nuclear osmium complex could be removed from a polymeric support after reaction. This suggests catalytic activity for this complex, particularly in the fixed state. Furthermore, a definite correlation was found to exist between polynuclearity and selectivity of heptanol formation. For iron, however, the cluster structure altered during the course of the reaction. 

Synonyms cas 112-23-2 formic acid, heptyl ester heptanol, formate n-heptyl methanoate Heptyl Heptoate... 

Heptanol, formate. See Heptyl formate Heptanolide-1,4 Heptan-4-olide Heptanolide-4,1. See y-Heptalactone... 

Synonyms Formic acid, heptyl ester Heptanol, formate n-Heptyl methanoate... 

FIGURE 4 18 The mechanism of formation of 1 bromoheptane from 1 heptanol and hydrogen bromide... 

Several procedures are used to control the ratios of cyclodextrins produced. One is addition of a substance to the reaction mixture that can gready affect the formation of one specific cyclodextrin over another. For example, in the presence of 1-decanol and 1-nonanol, a-cyclodextrin is produced almost exclusively whereas hexane or toluene promote the production of P-cyclodextrin. Conversely both cyclodextrins are produced simultaneously in the presence of 1-heptanol (2,4). 

The catalytic alcohol racemization with diruthenium catalyst 1 is based on the reversible transfer hydrogenation mechanism. Meanwhile, the problem of ketone formation in the DKR of secondary alcohols with 1 was identified due to the liberation of molecular hydrogen. Then, we envisioned a novel asymmetric reductive acetylation of ketones to circumvent the problem of ketone formation (Scheme 6). A key factor of this process was the selection of hydrogen donors compatible with the DKR conditions. 2,6-Dimethyl-4-heptanol, which cannot be acylated by lipases, was chosen as a proper hydrogen donor. Asymmetric reductive acetylation of ketones was also possible under 1 atm hydrogen in ethyl acetate, which acted as acyl donor and solvent. Ethanol formation from ethyl acetate did not cause critical problem, and various ketones were successfully transformed into the corresponding chiral acetates (Table 17). However, reaction time (96 h) was unsatisfactory. 

The addition of water and a non-hydrogen-bonding solvent to the reduction medium causes the reactions to shift toward the formation of alcohol products.313 For example, triethylsilane in a mixture of concentrated hydrochloric acid and acetonitrile (5 4) reduces 1-heptanal to 1-heptanol in quantitative yield after 3 hours at room temperature. In a mixture of triethylsilane in sulfuric acid, water, and acetonitrile (2 2 5), //-hep(anal gives a 97% yield of the same alcohol after 1.25 hours (Eq. 156).313... 

The enthalpy of isomerization of hquid 1-hexanol to either 2- or 3-hexanol is ca 15 kJ mol , and the enthalpy of isomerization of hquid 1 -heptanol to 2-, 3- or 4-heptanol is ca 13 kJ mol . From the experimental enthalpy of formation of 1 -hexyl hydroperoxide, the calculated enthalpy of formation of 2- and 3-hexyl hydroperoxide is ca —315 kJ moU , which is about 5-10 kJmoU more negative than their experimental values. As noted earlier, the measured enthalpies of formation of 2- and 3-heptyl hydroperoxide are about the same as that of 1-heptyl hydroperoxide, while that of 4-heptyl hydroperoxide is actually less negative than for its primary isomer. Using instead the above-derived enthalpy of formation of 1-heptyl hydroperoxide of —325 kJmoU , the enthalpy of formation of the secondary isomers would be ca —338 kJ moU. This value is very close to the experimental enthalpy of formation of 4-heptyl hydroperoxide, but 8 kJmoU less negative than the experimental values for 2- and 3-heptyl hydroperoxide. These latter enthalpies of formation are too negative compared to the experimental values for 2- and 3-hexyl hydroperoxide, with a methylene increment of ca 36 kJ mol . The derived values are more plausible. 

The enthalpies of formation of the heptanols were taken from K. B. Wiberg, D. J. Wasserman and E. Martin, J. Phys. Chem., 88, 3684 (1984). 

The enthalpies of formation of the saturated alcohols were taken from Reference 14 (2-, 3- and 4-heptanol) and K. B. Wiberg, D. J. Wasserman, E. J. Martin and M. A. Murcko, J. Am. Chem. Soc., 107, 6019 (1985) (1-methylcyclohexanol). The enthalpy of formation of 2-methylhex-l-ene-3-yn-2-ol is from Reference 32. The enthalpy of formation of sohd 2,5-dimethylhexane-2,5-diol is from Reference 2 and the enthalpy of vaporization (100.7 ... 

Marlipal 0 13/60/ cyclohexane Alcohol and formate dehydrogenases (ADH FDH) A 12-fold increase in ADH catalyzed reduction rates of 2-heptanone to S-2-heptanol was demonstrated in RMs. The NADH consumed in the reaction was regenerated by another enzyme FDH [23]... 

Eq. 4.54 shows the reaction of n-heptanol (151) with Pb(OAc)4 under high-pressured carbon monoxide with an autoclave to generate the corresponding 8-lactone (152). This reaction proceeds through the formation of an oxygen-centered radical by the reaction of alcohol (151) with Pb(OAc)4,1,5-H shift, reaction with carbon monoxide to form an acyl radical, oxidation of the acyl radical with Pb(OAc)4, and finally, polar cyclization to provide 8-lactone [142-146]. This reaction can be used for primary and secondary alcohols, while (3-cleavage reaction of the formed alkoxyl radicals derived from tertiary alcohols occurs. 

Property data from the literature (1-55,110,113,114,126,131,136,138-146) are given in Table 10-1. Since results for allyl alcohol and 1-heptanol are not available in the DIPPR project, critical constants for these compounds were selected from Yaws (44,47). Critical constants for the remaining compounds were selected from the DIPPR project (5). Additional property data such as acentric factor, enthalpy of formation, lower explosion limit in air and solubility in water are also available. The DIPPR (Design Institute for Physical Property Research) project (5) and recent data compilations by Yaws and co-workers (44-55) were consulted extensively in preparing the tabulation. 

The influence of structure on molecular association in the alcohols was shown by Smyth (24), who determined the dielectric constant and molar polarization of 22 isomeric octanols in the pure state. Only general conclusions can be drawn from these results. As Smyth says, associations in which the dipoles reinforce each other, giving high P and e, seem to occur when the OH group is at the end of a long C chain and remote from a branch in the chain—i.e., when linear multimer formation is most favored. When the OH group is in the middle of the chain and there is also branching at that point as in 4-methyl-4-heptanol, P is approximately half the value for 1-octanol, as would be expected if cyclic multimers predominate. 

It seems that multimer formation occurs with increasing ease in the series pentamethylethanol, 2,4-dimethyl-3-pentanol, 4-heptanol, cyclo-heptanol, 1-heptanol. Since we have detected the above differences between alcohols, three of which are secondary isomers, the process of association does not seem to depend on the class of alcohol. 

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