1- Heptanol bromide

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

Sketch a potential energy diagram for the reaction of 1 heptanol with hydrogen bromide paying careful attention to the positioning and structures of the intermediates and transition states... 

Mixtures of aldehydes with surfactants are active in preventing corrosion, in particular in the presence of mineral or organic acids [646]. The aldehyde may be trans-cinnamaldehyde. The surfactant may be N-dodecylpyridinium bromide or the reaction product of trimethyl-1-heptanol with ethylene oxide [645]. Such aldehyde and surfactant mixtures provide greater and more reliable corrosion inhibition than the respective compositions containing aldehydes alone. 

Heptanol-2 has been prepared by the action of w-amyl magnesium bromide on acetaldehyde,1 and by the reduction of methyl w-amyl ketone in alcoholic solution by means of sodium.2... 

Sn2 Reactions with epoxides and aziridines are also synthetically useful. An example of epoxide cleavage with an organocopper reagent with sp carbon moieties is the enantioselective synthesis of (3S, 4S)-4-methyl-3-heptanol (53), an elm bark beetle (Scolytus multistriatus) pheromone [42]. The chiral epoxy oxazolidine 51 [43], prepared from (R)-phenylglycinol, reacted with a propylmagnesium bromide-derived cuprate at —70 °C to afford the oxazolidine 52 in 74% yield (Scheme 9.12). Compound 52 was converted into the target molecular 53 by conventional procedures. 

Ketones carrying a sulfone substituent in the -position were subjected to enantioselective hydrogenation of the carbonyl group. With the heterogeneous Raney nickel catalyst, modified with tartaric acid and sodium bromide (see Section 2.3.1.1.), l-methylsulfonyl-2-butanone was reduced to (R)-l-methylsulfonyl-2-butanol, 1-methylsulfonyl-2-heptanone to (R)-l-methylsul-fonyl-2-heptanol, and l-methylsulfonyl-2-deeanone to (/ )-l-methylsulfonyl-2-decanol in 100% yield 67-71% ee51. 

Formation of 1-Bromoheptane from 1-Heptanol and Hydrogen Bromide 159... 

Unlike tertiary and secondary carbocations, methyl and primary carbocations are too high in energy to be intermediates in chemical reactions. However, methyl and primary alcohols are converted, albeit rather slowly, to alkyl halides on treatment with hydrogen halides. Therefore, they must follow a different meehanism, one that avoids carbocation intermediates. This alternative process is outlined in Mechanism 4.2 for the reaction of 1-heptanol with hydrogen bromide. 

As displayed in Figure 10.4, the ricinoleic acid (here the transesterification product, methyl ricinoleate) is subjected to a pyrolysis step. More specifically, the cracking pyrolysis takes place at 500-600 °C in presence of water vapour but in the absence of air to release undecenoic acid (methyl undecenoate) and heptaldehyde. The side product heptaldehyde is a source of several seven carbon-containing co-products such as heptanoic acid or heptanol. The main intermediate, methyl undecenoate, is further treated [9]. Firstly, it is hydrolysed to yield undecenoic acid. Then, it is reacted with hydrogen bromide in a nonpolar solvent to enable the reverse addition reaction, which forms bromoundecanoic acid. Finally, upon ammonia treatment, the crystalline solid 11-aminoundecanoic acid is formed and separated. 

HYDROGEN CHLORIDE AND HYDROGEN BROMIDE IN HEXANOL AND HEPTANOL... 

HYDROGEN CHLORIDE AND HYDROGEN BROMIDE IN HEXANOL AND HEPTANOL //ENGLISH TRANSLATION OF UKR. KHIM. ZH. 32 /8/ 801-6,1966.//... 

The heptanol (enanthol), which occurs on scission, is used for many different syntheses. The methyl undecylenate is saponified to the acid, to which hydrogen bromide is added across the double bond in an 02 initiated radical reaction to produce undecanoic acid. This is converted to 11-amino undecanoic acid by ammonolysis in aqueous dispersions, to which pure 11-bromoundecanoic acid can be added, since 10-bromoundecanoic acid cannot be ammonolyzed because of the secondary Br atom. Use of 3 kg of castor oil produces about 1 kg of nylon 11. 

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