Repozytorium
Wyszukaj
Kolekcje
Inne
Low-pressure carbonylation of benzyl bromide with palladium complexes modified with PNS (PNS=Ph2PCH2CH2C(O)NHC(CH3)2CH2SO3Li) or P(OPh)3. Structural identification of palladium-catalyst intermediate.
Autorzy
Rok wydania
2001
Czasopismo
Numer woluminu
77
Strony
245-249
DOI
10.1023/A:1013267915872
Kolekcja
Język
Angielski
Typ publikacji
Artykuł
The catalytic activities of two palladium complexes with water soluble phosphine PNS (PNS = Ph2PCH2CH2C(O)NHC(CH3)2CH2SO3Li) (I) and phosphite P(OPh)3 (II) were tested in the carbonylation of benzyl bromide in methanol at 40–50°C and 1 atm of CO. The first catalyst, (I), was formed in situ from PdCl2(cod) and PNS, the second one, (II), was based on the PdCl2(P(OPh)3)2 complex. At the ratio of [NEt3]:[PhCH2Br] equal to 2.5 the yields of phenylacetic acid methyl ester were 83–86% in the carbonylation with PNS and 100% in the carbonylation with P(OPh)3. The palladium catalyst with P(OPh)3 produced under the same conditions 70% of phenylacetic acid methyl ester in the carbonylation of benzyl chloride and 60% of 2-methylphenylacetic acid methyl ester in the carbonylation of 1-bromoethylbenzene. The lower rate of carbonylation of 1-bromoethylbenzyl bromide in comparison to that of benzyl bromide was explained by the lower rate of the substrate oxidative addition step leading to palladium benzyl complexes. Two palladium benzyl complexes, cis-PdBr(PhCH2)(P(OPh)3)2 and trans-PdBr(PhCH(Me))(P(OPh)3)2 have been isolated and characterized (X-ray, 31P and 1H NMR).
Słowa kluczowe
carbonylation, benzyl bromide, palladium catalyst, water soluble phosphine
Adres publiczny
https://doi.org/10.1023/A:1013267915872
Strona internetowa wydawcy
Podobne publikacje
Carbonylation of benzyl bromide to benzeneacetatic acid and its esters catalysed by water-soluble palladium complexes.
Trzeciak Anna M., Ziółkowski Józef J.
Structural studies of PdCl2L2 complexes with fluorinated phosphines, phosphines, and phosphinites as precursors of benzyl bromide carbonylation catalysts, and and X-ray crystal structure ofcis-PdCl2[PPh2(OEt)]2.
Trzeciak Anna M., Bartosz-Bechowski Hubert, Ciunik Zbigniew, Niesyty Katarzyna, Ziółkowski Józef J.
Catalytic activity of palladium complexes, PdCl2(COD) and PdCL2(P(OPh)3)2, in methoxycarbonylation of iodobenzene.
Trzeciak Anna M., Wojtków Wojciech, Ziółkowski Józef J.