Alcohols alcohol carbon atom

If one of the groups in the alcohol carbon atom is H, then another disconnection is ... 

Draw the product, and identify the three groups bonded to the alcohol carbon atom. One of the three will have come from the Grignard reagent, and the remaining two will have come from the ketone. 

Phenyl-2-butanol has a methyl group, an ethyl group, and a phenyl group (—Cgl ) attached to the alcohol carbon atom. Thus, the possibilities arc addition of ethylmagnesium bromide to acetophenone, addition of methylmagnesium bromide to propiophenone, and addition of phenylmagnesimn bromide to 2-butanone. 

Wuts and co-workers recently reported that the Vilsmeier reagent is superior to thionyl chloride for the cyclodehydration of primary and secondary p-hydroxy amides to prepare oxazolines, in particular, for oxazoline 18b, which is used in Taxol synthesis (Scheme 8.10). Some other examples are shown in Table 8.5 (Fig. 8.3). As expected, inversion of configuration at the alcohol bearing carbon atom is observed. Of the examples examined, serine afforded low yields due to the formation of dehydroalanine. The reaction is conveniently carried out in pyridine at room temperature. p-Chloro amides are also formed, which can be converted to the oxazoline with DBU, generally using the same mixture without isolation. The... 

To investigate the effect of alcohol hydrogen-bond donor (HBD) strength in a systematic way, a series of modifiers possessing a common 4-teri-octylphenoxy ethanol core element were prepared, in which the properties of the substituent attached to the alcohol carbon atom were varied. These modifiers were evaluated with respect to both the cesium extraction strength they afforded when used in combination with BC6 and the HBD strength of the solvent as assessed using the solvatochromic parameter E. ... 

The mechanism of oxidation takes place with retention of stereochemistry at the alcohol s carbon atom and so the overall... 

In an alcohol, the carbon atom bonded to the hydroxyl group, (p. 426)... 

Strategy Draw the product, and identify the three groups bonded to the alcohol carbon atom. 

In addition to the products mentioned hitherto, the formation of various condensed products was also reported in the liquid phase and in solu-tion in addition, the formation of cyclohexanone pinacoP and caproic acid in cyclohexanol and water solutions, respectively, was observed. Moreover, aliphatic alcohols with carbon atom numbers equal to those of the original ketones were found in the liquid phase and also in solution It is probable that these products were formed by the interaction between the excited and the normal ketone molecules or in the reaction of the excited ketone with the solvent. These processes may be symbolized as... 

The compound 1-propanol is a primary alcohol The carbon atom to which the —OH group is bonded has exactly one other carbon atom attached to it. The isomeric compound 2-propanol is a secondary alcohol because the carbon atom to which the —OH group is attached has two carbon atoms (in the two methyl... 

Whitesell and Minton have synthesized (- )-xylomollin (408), the only trans-fiised iridoid, from the racemic bicyclic diene 409. Control of the stereochemistry was effected in the first step by addition of the glyoxylate 410. The two products were separated and the major one, 411, was reduced with lithium aluminum hydride. Conversion of the primary alcohol to a methyl group, with concomitant inversion of stereochemistry at the secondary alcohol carbon atom was carried out by protection of the primary alcohol function (fert-butyldimethylsilyl), tosylation of the secondary hydroxyl, then removal of the silyl group with formation of an epoxide with inversion, and reduction (LiEtaBH) of the epoxide. The remaining steps are shown in Scheme 36. It remains to point out that isoxylomoUin (412) was produced preferentially, and is indeed formed from xylomollin (408) slowly in methanolic solution. ... 

In primary alcohols, the carbon atom bearing the —OH group has two hydrogen atoms, except methanol, which has three. 

Example 5.5. Oxidation of paraffins to secondary alcohols (see also Section 10.6.2). Alcohols can be produced by oxidation of paraffins with air or oxygen at moderate temperatures (typically 120 to 180° C) in the presence of borate esters or boroxines [16-19]. These intercept the alkyl hydroperoxide, the first oxidation product, preventing it from generating radicals that would cause further degradation including scission of carbon-carbon bonds and produce aldehydes, ketones, and acids. The peroxy borates so formed then are hydrolyzed to yield the alcohol. The carbon atoms at the chain ends are largely immune to oxidation, so the product consists predominantly of isomeric secondary alcohols. 

The mechanism of oxidation takes place with retention of stereochemistry at the alcohol s carbon atom and so the overall reaction is stereospecific (Following fig.). Note that the reaction is stereospecific such that the alcohol group is trans to the methyl group in the product. However, it is not enantiospecific and both enantiomers are obtained in equal amounts (a racemate). 

The alcohol carbon atom may also be a saturated carbon atom adjac ent to an alkenyl or alkynyl group, or the carbon atom may be a saturated carbon atom that is attached to a benzene ring ... 

FIGURE 6 The global minimum structure of the dimethyl-nitramine complex with methyl alcohol. The carbon atoms are gray, hydrogens—white, nitrogens—blue, and oxygens—red. (From Bukowski etal., 1999.)... 

Interestingly, the configuration on the chiral alcohol carbon atom has only a minor influence on the in vitro CatA activity, with the stereoisomer 13 having lost approximately a factor of 2 compared to 12. 

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