Alcohols, hydroaromatic

In summary, the most popular hydrogen donors for the reduction of ketones, aldehydes and imines are alcohols and amines, while cyclic ethers or hydroaromatic compounds are the best choice for the reduction of alkenes and alkynes. 

Cyclic ketones were reduced to opticaHy active cyclic alcohols by biochemical methods. Incubation of 2,3-benzosuberone with Cryptococcus macerans gave 27% conversion to the optically active (— )-S-2,3-benzo-1 -cycloheptanol. Other hydroaromatic ketones were reduced, although in low conversions (2-... 

Palladium is the most active and most frequently used catalyst in transfer hydrogenations.77 78 Cyclohexene, a cheap, readily available, highly reactive molecule, is the preferred donor compound. Alternatively, tetralin and monoterpenes and, in general, any hydroaromatic compound, may be used. Mainly alcohols are employed as the donor with Raney Ni. 

Multiple intramolecular ring closures of aryl-substituted unsaturated long chain alcohols, acids, acid chlorides and ethers in the presence of Friedel-Crafts catalysts have been extensively employed to synthesize polynuclear hydroaromatic hydrocarbons and polycyclic ketones. This is illustrated by two examples shown in equations (112) and (113). The application of stereospecific cycloalkylations in approaching the synthesis of complex organic molecules has been reviewed by Barclay. ... 

This primarily obtained compound may by different reactions be converted into other hydroaromatic and aromatic substances. If, e.g., the dimethylcyclohexenone be reduced, the ketone group is converted into the secondary alcohol group, at the same time the double union is severed, and two hydrogen atoms are added on, so that there is obtained an alcohol derivative of hexahydro-benzene or -xylene. 

The extraction of peat(s) and lignite(s) with benzene or benzene-methanol mixtures followed by fractionation of the crnde extract with diethyl ether or hot ethyl alcohol yields Montan waxes and resins (Table 11.3) and has actnally been nsed commercially. The waxes consist mostly of aliphatic (C24-C32) acids and the corresponding esters as well as C24-C32 alcohols, while the resins (which resemble colophy or hanri gnms) are derivatives of mono- and dibasic C,2-C2o acids with aromatic/ hydroaromatic nnclei (e.g., abietic acid). 

At a greater distance pollinators may be lured by flower scents. These flower volatiles cover a wide range of chemical structures (Table 72). They are usually complex mixtures possessing hundreds of constituents including simple aliphatic alcohols, ketones and esters as well as aromatic, hydroaromatic, and heterocyclic compounds. Scents are of special significance for pollination of flowers by... 

Notes The reaction is suitable for the detection of alcohols of Cs and higher. A positive reaction is also given by hydroaromatic alcohols, phenols, and all compoimds with a double bond in the chain or in the ring, as well as compounds with a three-membered ring. Some ketones (acetone, methyl ethyl ketone, cyclohexanone) and aldehydes (acetaldehyde, propionaldehyde, isovaleraldehyde) also react positively. As regards the reaction with esters of acids and glycols, the data in the literature are conflicting. 

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