TY - JOUR
T1 - Synthesis and structures of complexes with axially chiral isoquinolinyl-naphtholate ligands
AU - Howard, Ruth H.
AU - Alonso-Moreno, Carlos
AU - Broomfield, Lewis M.
AU - Hughes, David L.
AU - Wright, Joseph A.
AU - Bochmann, Manfred
PY - 2009
Y1 - 2009
N2 - The synthesis of axially chiral ligands 1-(3',6'-di-t-butyl-2'-hydroxy-1'-naphthyl)-3-R-isoquinoline (R = H, Pri, But) (LR-H) is described. Ligands with unsubstituted isoquinolinyl rings tend to give 1:2 metal complexes. The syntheses and crystal structures of Li2(LH)2(THF)2 (9), (LH)2Ti(OPri)2 (12), Zn(LH)2 (13) and [Mg(LH)2]2 (14) are reported. Complex formation is highly stereoselective; the ligands in 1:2 complexes have the same stereochemistry (i.e. R,R and S,S but not R,S), whereas in the binuclear magnesium compound 14 the bridging and non-bridging ligands LH have opposite stereochemistry. The reaction of LH-H with Pd(acac)2 afforded the N,O chelate Pd(acac)(LH) (10), whereas towards K2PtCl4 the same ligand acts as an N-donor only, to give trans-PtCl2(LH-H)2 (11) in which the OH groups are hydrogen-bonded to one of the two chloride ligands. The more bulky ligand with a t-butyl substituent in the 3-position of the isoquinolinyl ring reacts with zinc and magnesium bis(amides) to give the mixed-ligand species (LBu)ZnN(SiMe3)2 and (LBu)MgN(SiMe3)2, respectively, which catalyse the ring-opening polymerisation of e-caprolactone (CL) and rac-lactide (LA).
AB - The synthesis of axially chiral ligands 1-(3',6'-di-t-butyl-2'-hydroxy-1'-naphthyl)-3-R-isoquinoline (R = H, Pri, But) (LR-H) is described. Ligands with unsubstituted isoquinolinyl rings tend to give 1:2 metal complexes. The syntheses and crystal structures of Li2(LH)2(THF)2 (9), (LH)2Ti(OPri)2 (12), Zn(LH)2 (13) and [Mg(LH)2]2 (14) are reported. Complex formation is highly stereoselective; the ligands in 1:2 complexes have the same stereochemistry (i.e. R,R and S,S but not R,S), whereas in the binuclear magnesium compound 14 the bridging and non-bridging ligands LH have opposite stereochemistry. The reaction of LH-H with Pd(acac)2 afforded the N,O chelate Pd(acac)(LH) (10), whereas towards K2PtCl4 the same ligand acts as an N-donor only, to give trans-PtCl2(LH-H)2 (11) in which the OH groups are hydrogen-bonded to one of the two chloride ligands. The more bulky ligand with a t-butyl substituent in the 3-position of the isoquinolinyl ring reacts with zinc and magnesium bis(amides) to give the mixed-ligand species (LBu)ZnN(SiMe3)2 and (LBu)MgN(SiMe3)2, respectively, which catalyse the ring-opening polymerisation of e-caprolactone (CL) and rac-lactide (LA).
U2 - 10.1039/b907982c
DO - 10.1039/b907982c
M3 - Article
SP - 8667
EP - 8682
JO - Dalton Transactions
JF - Dalton Transactions
SN - 1477-9226
IS - 40
ER -