Ketones alcohol synthesis from

Scheme 4.9. Synthesis of Alcohols, Aldehydes, Ketones, and Amines from... 

The production of optically active cyanohydrins, with nitrile and alcohol functional groups that can each be readily derivatized, is an increasingly significant organic synthesis method. Hydroxynitrile lyase (HNL) enzymes have been shown to be very effective biocatalysts for the formation of these compounds from a variety of aldehyde and aliphatic ketone starting materials.Recent work has also expanded the application of HNLs to the asymmetric production of cyanohydrins from aromatic ketones. In particular, commercially available preparations of these enzymes have been utilized for high ee (5)-cyanohydrin synthesis from phenylacetones with a variety of different aromatic substitutions (Figure 8.1). 

Mixed C4 olefins (primarily iC4) are isolated from a mixed C olefin and paraffin stream. Two different liquid adsorption high-purity C olefin processes exist the C4 Olex process for producing isobutylene (iCf ) and the Sorbutene process for producing butene-1. Isobutylene has been used in alcohol synthesis and the production of methyl tert-butyl ether (MTBE) and isooctane, both of which improve octane of gasoHne. Commercial 1-butene is used in the manufacture of both hnear low-density polyethylene (LLDPE) and high-density polyethylene (HDPE)., polypropylene, polybutene, butylene oxide and the C4 solvents secondary butyl alcohol (SBA) and methyl ethyl ketone (MEK). While the C4 Olex process has been commercially demonstrated, the Sorbutene process has only been demonstrated on a pilot scale. 

In recent years, dioxiranes have become workhorses for a variety of selective transformations in organic synthesis, from epoxidation of alkenes to the conversion of alcohols into fee corresponding ketones <99CJC308>. Dioxirane-mediated epoxidation continues to be the method of choice for complex substrates wife acid-sensitive functionality. Thus, fee dimethyl-dioxirane (DMD)-mediated epoxidation of the silylated stilbene lactam 159 has been reported as a key step in fee synthesis of protoberberines <99JOC877>. 

So, at the beginning of the 25-year period here commemorated, alcohols, glycols, aldehydes, and ketones, chlorinated hydrocarbons, esters, and ethers—all so vital in their direct uses or as chemical building blocks—were beginning to be produced by synthesis from hydrocarbons provided by the already well-grown petroleum and natural gas industries. Subsequent developments came in rapid succession, with remarkably little in-... 

An interesting case of interproduct competition is that of the four original lacquer solvents—ethyl alcohol, butyl alcohol, ethyl acetate, and butyl acetate. These were once produced mainly by fermentation processes, but today all are also produced by synthesis from petroleum hydrocarbons. Moreover, in the past 30 years solvents have been developed from petroleum sources which are competing successfully with these materials even though the new compounds are not identical in all properties isopropyl alcohol competes with ethyl alcohol methyl isobutyl carbinol and n-propyl alcohol can replace butyl alcohol methyl ethyl ketone to a large extent supplants ethyl acetate and methyl isobutyl ketone can be substituted for butyl acetate. Thus, petroleum aliphatic chemicals have served both by displacement of source and replacement of end product to supplement and to compete with the fermentation solvents. 

E Keinan, EK Hafeli, KK Seth, RR Lamed. Thermostable enzymes in organic synthesis. 2. Asymmetric reduction of ketones with alcohol dehydrogenase from Ther-moanaerobium brockii. J Am Chem Soc 108 162-168, 1986. 

C-(w-propyl)-N-phenylnitrone to N-phenylmaleimide, 46, 96 semicarbazide hydrochloride to ami-noacetone hydrochloride, 45,1 tetraphenylcyclopentadienone to diphenyl acetylene, 46, 44 Alcohols, synthesis of equatorial, 47, 19 Aldehydes, aromatic, synthesis of, 47,1 /8-chloro-og3-unsaturated, from ketones and dimethylformamide-phosphorus oxychloride, 46, 20 from alkyl halides, 47, 97 from oxidation of alcohols with dimethyl sulfoxide, dicyclohexyl carbodiimide, and pyridinium trifluoroacetate, 47, 27 Alkylation, of 2-carbomethoxycyclo-pentanone with benzyl chloride, 45, 7... 

For the production of chiral hydrophobic alcohols, FDH from C. boidinii was combined with an NAD+-dependent alcohol dehydrogenase (ADH) from Rhodo-coccus erythropolis. As a first example for the production of hydrophobic alcohols, an enzyme membrane reactor (EMR) was used for the synthesis enantiomerically pure (S)-1 -phenylpropan-2-ol and some related structures out of their corresponding ketones [42]. 

Fig. 40 Concept for the two-step synthesis of enantiomerically pure (S)-epoxides out of aliphatic 1-halogenated 2-ketones. The ketone was reduced by a recombinant whole-cell catalyst bearing alcohol dehydrogenase from Lactobacillus kefir (LKADH) and glucose dehydrogenase (GDH) for regeneration of NADPH. Base-induced cyclization of the enantiomerically pure (5)-(3-halohydrin intermediate gave the desired (S)-epoxides in high yield and enantiomeric purity (>99% ee)...

The last step of the synthesis is a reductive amination of a ketone that is formed by oxidation of the corresponding alcohol. The alcohol results from the Grignard reaction between cyclopentylmagnesium bromide and propylene oxide. 

Propose suitable methods for the synthesis of optically active alcohol 1 from its corresponding ketone. 

Cabarrocas G, Ventura M, Maestro M, Mahia J, Villalgordo JM (2001) Synthesis of novel optically pure quinolyl-P-amino alcohol derivatives from 2-amino thiophenol and chiral a-acetylenic ketones and their IBX-mediated oxidative cleavage to IV-Boc quinolyl carboxamides. Tetrahedron Asymmetry 12 1851-1863... 

Synthesis From Alcohols.— The general methods of synthesis of aromatic aldehydes and ketones are several. The aldehydes may be prepared by the direct oxidation of the corresponding primary alcohol, usually with dilute nitric acid, e.g.. 

Derivatives of Menthene.— The most important alcohols and ketones derived from the menthene unsaturated group of terpenes are terpineol, di-hydro carveol, di-hydro carvone and pulegone. The first one, the alcohol terpineol, occurs in its dextro form in cardamon oil and marjoram oil, in its leoo form in neroU oil and in its inactive form in cajeput oil. The constitution is proven by Perkin s synthesis from As-tetra-hydro para-toluic acid by means of the Grignard reaction. 

The stereochemical outcome of the addition of carbanions to ketones yielding tertiary alcohols (or secondary alcohols in the case of aldehydes) is variable and depends on the substrate, the counterion and the solvent. Numerous applications of this strategy to natural product synthesis from carbohydrates can be found in the literature and this approach was fruitful in pioneering syntheses of polyketide-type products. Here again, the template effect of the sugar plays a tremendous role in the stereochemical outcome of the reaction. Chelation controlled nucleophilic addition can also be used to form chiral centers in a highly predictable way. 

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