Mika Kettunen

Synthesis of new chiral diimine palladium(II) and nickel(II) complexes bearing oxazoline- and myrtanyl-based nitrogen ligands. Crystal structure of the C2-symmetric complex [{(1R,2S)-inda-box}PdCl2]

Abstract A synthesis of new chiral dihalo palladium(II)-(5, 7) and nickel(II) (6, 8) complexes bearing the ligands N,N′-bis{(−)-(cis)-myrtanyl}butylene-2,3-diimine (BMDI, 3) and the conformationally constrained bisoxazoline ligand ((1R,2S)-inda-box, 4) is described. Reaction of [(TMEDA)Pd(CH3)Cl] (TMEDA: N,N,N′,N′-tetramethylethylenediamine) with 4 followed by chloride abstraction with NaB(Arf)4 in the presence of CH3CN afforded the solvent stabilized, monoalkyl complex [(4)Pd(NCCH3)(CH3)]B(Arf)4 (9) (Arf: 3,5-bis(trifluoromethyl)benzene). The solid state structure of the dichloro palladium(II) complex [{(1R,2S)-inda-box}PdCl2] (7) was determined by X-ray structure analysis.

Homo- and copolymerization of strained cyclic olefins with new palladium(II) complexes bearing ethylene-bridged heterodonor ligands

Amorphous and high molar mass polymers of norbornene and phenylnorbornene (endo/exo ratio of 80/20) were prepared by the use of new dicationic palladium(II) single-component catalysts of the general type [Pd(L∩L)(NCCH 3 ) 2 ](BF 4 ) 2 . [(L∩L) = 2-(diphenylarsino)-1-(methylthio)ethane (S∩As, 1) (4), 2-diphenylphosphino)-1-methylthio)ethane (S∩P, 2) (5), 1, 2-bis(diphenylphosphino)ethane (P∩P, 3) (6). With increasing the trans influence of the donor atom in the ligands (P>As>S) the polymerization activity of the catalysts towards polymerization of norbornene increases instantly. Both the molecular weight and the thermal behavior of the polymer can be tailored using ethene as chain transfer agent. Catalyst 4 is also active towards the alternating copolymerization of carbon monoxide and norbornene. The isolated copolymer is highly soluble in toluene, THF and chlorinated solvents. The DSC measurement of the norbornene-carbon monoxide copolymer showed a melting temperature (T m ) of 241°C (ΔH f = 47.3 J/g) and a glass transition temperature (T g ) of 161°C which is about 170°C lower compared to the homopolynorbornene (T g ≃ 330°C).

Hydroformylation of cyclopentenes, novel strategy for total synthesis of carba-D-fructofuranose

Abstract Carba- d -fructofuranose ( 2a ) was synthesized in 3 steps from cyclopentene 3 . Compound 3 was prepared in 90% yield from commercially available 2,3,5-tri- O -benzyl- d -arabinose. The C-5 hydroxylmethyl unit was incorporated into 3 via hydroformylation using Wilkinsons catalyst. Reduction and hydrogenation afforded carba- d -fructofuranose ( 2a ).

Practical Method for 2‐Hydroxyphenylketimine Synthesis

Abstract A series of hydroxyphenylketimines, of which 15 are new, was synthesized in methanol at high temperature (200°C) using a sealed steel reactor. This reaction setup especially enhances the synthesis of 2‐hydroxyphenylketimines, with yields up to six times higher than those obtained with the conventional acid‐catalyzed method under refluxing conditions. In fact, some imines were achievable only by the autoclave method.

Hydroformylation of glycals using a rhodium(I)(acac)(CO)2 catalyst

Abstract The hydroformylation of glycals was achieved using Rh(I)(acac)(CO) 2 catalyst. For glucals, the C-2 formyl pyran was the major product whilst for galactal an equimolar mixture of the C-2 and C-1 regioisomers were observed.