4- benzylic acid

Benzylic acid rearrangement, 836 Benzylic carbocation, electrostatic potential map of, 377 resonance in, 377 SN1 reaction and, 376-377... 

Treatment of 6-arylidenehydrazino-3-alkyl-5-nitrouracils 510 with etha-nolic KOH caused a benzylic acid type of rearrangement to give 511, which were alkylated to give 512, whose cyclization with diethyl azodicar-boxylate gave (80H1295) 513 by intramolecular cycloaddition through valence isomerization and then aromatization with diethyl azodicarboxylate (Scheme 107). 

The oxygen derivative 39a has its origins in the acyloin reduction product of diethyl succinate 45. A benzylic acid type of rearrangement of in situ formed... 

Rearrangement of benzil to benzylic acid via aryl migration. 

Metabolism - The metabolic pathway of trospium in humans has not been fully defined. Of the 10% of the dose absorbed, metabolites account for approximately 40% of the excreted dose following oral administration. The major metabolic pathway is hypothesized as ester hydrolysis with subsequent conjugation of benzylic acid to form azoniaspironortropanol with glucuronic acid. Cytochrome P450 is not expected to contribute significantly to the elimination of trospium. 

On treatment of the quinone (109) with NaOH in a dioxane-water mixture (1 1) at 100° for several days a benzylic acid rearrangement takes place giving phenanthro-[3,4-c]fluorene (110) in 52% yield U3>. 

Fluorodecarboxylation.1 Reaction of alkanoic acids with XeF2 in CH2C12 can result in alkyl fluorides by replacement of the COOH group by F. Yields are highest with primary, tertiary, and benzylic acids. Aryl or vinylic acids do not undergo this reaction. 

Benzoic acid triozonide was prepd by treating the acid in chlf and CC14 at 0-15° with ozone for 20 hrs. One sample of the triozonide exploded in a desiccator. This triozonide was less stable than that of either benzylic acid, CgHg.CH2.CO-OH or of phenethylic(phenyl-(3-ethyl) acid, Cgf -CHj.CHj.COOH, which were obtd in lower yields Refs l)Beil- not found 2)H.Ruppe H.Hirsch-... 

Keywords benzil, alkyli metal hydroxide, benzylic acid rearrangement, benzylic acid... 

On the basis of these results, the benzyl-benzylic acid rearrangement 179 180 -> 181 should occur with stereoelectronic control. The stereochemistry of the transposition should be as depicted by 182 +183. 

The partial oxidation of alcohols, to afford carbonyl or carboxylic compounds, is another synthetic route of high industrial interest For this, scC02 was investigated as a reaction medium for the aerobic oxidation of aliphatic, unsaturated, aromatic and benzylic acids with different catalytic systems, mainly based on the use of noble metals, both in batch [58-64] and in continuous fixed-bed reactors [65-70]. In this context, very promising results have been obtained when studying the catalytic activity of supported palladium and gold nanoparticles in the oxidation of benzyl alcohol to benzaldehyde these allowed conversions and selectivities in excess of 90% to be achieved [71-73]. 

W When abstraction of the tx-hydrogen by base is difficult, if not impossible, reaction occurs by a benzylic acid-like rearrangement (Wamhoff, E. W., Wond, C. M., Tai, W. T. J. Am. Chem. Soc. 90, 514 (1968) and references therein). 

B.8 Benzylic acid (degradation product of BZ) Not used as spiking chemical in proficiency test 1 to 10 ... 

The fluorodecarboxylation reaction, with a proposed mechanism where the acid is initially converted to a fluoroxenon ester, proceeds best with primary, tertiary and benzylic acids. Fluoroxenon esters of primary and secondary acids react under ionic conditions ... 

If the MeO group is replaced by a leaving group such as MsO, it can exercise the pull and the carbonyl can provide the push after it has been attacked by a nucleophile. This next five-membered cyclic ketone fragments on treatment with base—can you detect hints of the benzylic acid rearrangement ... 

Because of their relatively high reactivity, the foregoing structures often appear as transient intermediates in a series of reactions rather than as end products. Several of the documented reactions of these intermediates include rearomatization (e.g., reduction to catechol and hydroquinone derivatives), further oxidation to mono- and dicarboxylic acids (see below), benzylic acid rearrangements (Corbett 1966, Corbett and Fooks 1967), cycloaddition reactions (Teuber et al. 1966), and various condensation reactions (Erdtman and Granath 1954). The last-named processes, which are accelerated in acidic and basic media, often give rise to structurally complex and poorly defined materials. 

An enantioselective synthesis of TIQ-1-carboxylic acids 91a,b has recently been reported (279). Hydrolysis of the optically active methyl ether enantiomer of hydantoin 103 was accomplished by 20% sodium hydroxide in refluxing methyl cellosolve and led to the dimethyl ether analog of 91a, which was used to establish the absolute configuration of the products. Amino acids 91a,b have also been prepared by chemical resolution of the N,0-benzylated acid 108 with optically active 1-phenylethylamines. Catalytic debenzylation of enantiomer 109a gave... 

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