FRINK Linked Data Fragments server

Matches in SemOpenAlex for { <https://semopenalex.org/work/W1970591738> ?p ?o ?g. }

• W1970591738 endingPage "178" @default.
• W1970591738 startingPage "169" @default.
• W1970591738 abstract "The reduction of mandelic acid derivatives (ArCHOHCOOH) to phenylacetic acid derivatives by carbon monoxide catalyzed by a PdHCl system easily occurs when the aromatic ring is para-substituted with a hydroxy group. Other electron-releasing substituents such as a methoxy group have a much lower promoting effect. The reaction practically does not occur with mandelic acid. A compound of Pd(II), such as PdX2, [Pd(1,3-η-C3H5)Cl]2] or PdX2(PPh3)2 (X  Cl, AcO) can be used as catalyst precursor. The reaction occurs to an appreciable extent only in the presence of HCl. Under the reaction conditions tested (70–110 °C, 50–100 atm of carbon monoxide, benzene-ethanol as reaction medium, [Pd(II)] = 10−3−10−2 M, substrate/HCl/Pd = 100:50:1) decomposition to Pd metal occurs. Pd/C can also be used: it gives practically the same results as the precursors listed above. The key steps of the proposed catalytic cycle are: (i) the chloride ArCHClCOOR (R  H, Et), formed in situ by substitution of the α-hydroxy group of ArCHOHCOOR upon reaction with HCl, oxidatively adds to a Pd(O) species with formation of a catalytic intermediate having a Pd[CH(Ar)COOR] moiety; (ii) the PdC σ-bond of this species inserts carbon monoxide, yielding an acyl intermediate of the type Pd[COCH(Ar)COOR]; (iii) nucleophilic attack of ROH on the carbon atom of the carbonyl ligand yields a phenylmalonic acid derivative which splits off CO2 yielding the final product, ArCH2COOR. Alternatively, H+ may react with the intermediate formed in step (i), yielding directly the final product and a Pd(II) species, which is reduced by CO to Pd(O), which starts another catalytic cycle. The promoting effect of the hydroxy substituent in para position is discussed in terms of resonance structures. This reaction is compared with the carbonylation of aromatic aldehydes to ArCH2COOR, catalyzed by a PdPPh3HCl system. Also in this case there is a marked promoting effect of a hydroxy substituent in the para position. However, the carbonylation of the aldehydes occurs only in the presence of both PPh3 and HCl, at variance with the reductive carbonylation described in this paper, where this ligand does not play any major role." @default.
• W1970591738 created "2016-06-24" @default.
• W1970591738 creator A5010518446 @default.
• W1970591738 creator A5080902862 @default.
• W1970591738 date "1992-09-01" @default.
• W1970591738 modified "2023-10-14" @default.
• W1970591738 title "Synthesis of arylacetic acid derivatives via reduction of mandelic acid derivatives by carbon monoxide catalyzed by a Pd-HCl system" @default.
• W1970591738 cites W1538688069 @default.
• W1970591738 cites W1966168095 @default.
• W1970591738 cites W1976619085 @default.
• W1970591738 cites W1985768828 @default.
• W1970591738 cites W1992276844 @default.
• W1970591738 cites W1994020610 @default.
• W1970591738 cites W2008263542 @default.
• W1970591738 cites W2014157917 @default.
• W1970591738 cites W2022911371 @default.
• W1970591738 cites W2026639147 @default.
• W1970591738 cites W2031545212 @default.
• W1970591738 cites W2038703826 @default.
• W1970591738 cites W2041356486 @default.
• W1970591738 cites W2046070830 @default.
• W1970591738 cites W2051887387 @default.
• W1970591738 cites W2053656092 @default.
• W1970591738 cites W2055927979 @default.
• W1970591738 cites W2061369629 @default.
• W1970591738 cites W2063507951 @default.
• W1970591738 cites W2073818637 @default.
• W1970591738 cites W2075956615 @default.
• W1970591738 cites W2090108565 @default.
• W1970591738 cites W2111085571 @default.
• W1970591738 cites W2123225572 @default.
• W1970591738 cites W2317370041 @default.
• W1970591738 cites W2322709485 @default.
• W1970591738 cites W2324362250 @default.
• W1970591738 cites W2952746732 @default.
• W1970591738 doi "https://doi.org/10.1016/0304-5102(92)80119-2" @default.
• W1970591738 hasPublicationYear "1992" @default.
• W1970591738 type Work @default.
• W1970591738 sameAs 1970591738 @default.
• W1970591738 citedByCount "9" @default.
• W1970591738 countsByYear W19705917382018 @default.
• W1970591738 crossrefType "journal-article" @default.
• W1970591738 hasAuthorship W1970591738A5010518446 @default.
• W1970591738 hasAuthorship W1970591738A5080902862 @default.
• W1970591738 hasConcept C155647269 @default.
• W1970591738 hasConcept C161790260 @default.
• W1970591738 hasConcept C178790620 @default.
• W1970591738 hasConcept C178907741 @default.
• W1970591738 hasConcept C185592680 @default.
• W1970591738 hasConcept C2776568683 @default.
• W1970591738 hasConcept C2778735290 @default.
• W1970591738 hasConcept C512735826 @default.
• W1970591738 hasConceptScore W1970591738C155647269 @default.
• W1970591738 hasConceptScore W1970591738C161790260 @default.
• W1970591738 hasConceptScore W1970591738C178790620 @default.
• W1970591738 hasConceptScore W1970591738C178907741 @default.
• W1970591738 hasConceptScore W1970591738C185592680 @default.
• W1970591738 hasConceptScore W1970591738C2776568683 @default.
• W1970591738 hasConceptScore W1970591738C2778735290 @default.
• W1970591738 hasConceptScore W1970591738C512735826 @default.
• W1970591738 hasIssue "2" @default.
• W1970591738 hasLocation W19705917381 @default.
• W1970591738 hasOpenAccess W1970591738 @default.
• W1970591738 hasPrimaryLocation W19705917381 @default.
• W1970591738 hasRelatedWork W1772767189 @default.
• W1970591738 hasRelatedWork W1998672638 @default.
• W1970591738 hasRelatedWork W2037969415 @default.
• W1970591738 hasRelatedWork W2071516854 @default.
• W1970591738 hasRelatedWork W2073303399 @default.
• W1970591738 hasRelatedWork W2129821675 @default.
• W1970591738 hasRelatedWork W2147427301 @default.
• W1970591738 hasRelatedWork W2336439539 @default.
• W1970591738 hasRelatedWork W2565526008 @default.
• W1970591738 hasRelatedWork W2997403453 @default.
• W1970591738 hasVolume "75" @default.
• W1970591738 isParatext "false" @default.
• W1970591738 isRetracted "false" @default.
• W1970591738 magId "1970591738" @default.
• W1970591738 workType "article" @default.