Premium
On the Use of Non‐Symmetrical Mixed PCN and SCN Pincer Palladacycles as Catalyst Precursors for the Heck Reaction
Author(s) -
Consorti Crestina S.,
Ebeling Gunter,
Flores Fabricio R.,
Rominger Frank,
Dupont Jairton
Publication year - 2004
Publication title -
advanced synthesis and catalysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.541
H-Index - 155
eISSN - 1615-4169
pISSN - 1615-4150
DOI - 10.1002/adsc.200303228
Subject(s) - chemistry , pincer movement , aryl , heck reaction , catalysis , medicinal chemistry , coupling reaction , palladium , polymer chemistry , stereochemistry , organic chemistry , alkyl
Abstract The mixed pincer palladacycles (Me 2 NCH 2 (Cl)CCCH 2 CH 2 Y‐κ N ,κ C ,κ Y )PdCl ( 1 , Y=PPh 2 ; 2 , OPPh 2 ) and ( t ‐BuSCH 2 CH 2 CC(Cl)( o‐ NC 5 H 4 )‐κ S ,κ C ,κ N )PdCl 3 have been obtained in high yields by chloropalladation of heterosusbstituted alkynes Me 2 NCH 2 CCCH 2 CH 2 PPh 2 , Me 2 NCH 2 CCCH 2 CH 2 OPPh 2 and t ‐BuSCH 2 CH 2 CC( o‐ NC 5 H 4 ), respectively. The molecular structures of 1 and 3 have been ascertained by means of X‐ray diffraction analysis. The catalytic properties of these mixed donor group pincer‐type palladacycles have been evaluated in the arylation of olefins (Heck reaction). The pincer palladacycle 1 is highly active for the coupling of aryl iodides and aryl bromides with n‐ butyl acrylate. In contrast it is only moderately active for the coupling of aryl chlorides substituted with electron‐withdrawing groups and inactive for the coupling of electron neutral and electron deactivated aryl chlorides.