Structural and Electrochemical Studies of Copper(I) Complexes with Diethoxyphosphoryl‐1,10‐phenanthrolines

Abstract

The first organocatalytic enantioselective approach to precursors of tubuvaline (pre‐Tuv) is presented employing a prolinamide‐catalyzed aldol reaction of easily accessible thiazole‐carbaldehyde with methyl isopropyl ketone “on water” in excellent yield as well as regio‐ and enantioselectivities. The analogues of pre‐Tuv were achieved using an L‐proline‐catalyzed direct asymmetric aldol reaction of substituted thiazole‐carbaldehydes with acetone. A direct and flexible approach to the tubavaline (Tuv) core of tubusylins has been established employing the reductive amination of the pre‐Tuv species. The key aldol reaction should greatly expand the potential of this strategy to the synthesis of natural product tubulysins and a range of analogues.

Immobilization of copper complexes with (1,10-phenanthrolinyl)phosphonates on titania supports for sustainable catalysis

“…Recently, we reported the synthesis of air and moisture stable copper(I) complexes with (diethoxyphosphoryl) phenanthroline and triphenylphosphine ligands (1a-3a) which catalyzed C-C and C-Het (Het ¼ N, P) cross-coupling reactions. 64,65,81 These complexes could also be useful for the preparation of heterogeneous catalysts if the diethoxyphosphoryl substituent could be transformed into more reactive phosphonic acid or bis(trimethylsiloxy)phosphoryl groups (Scheme 1). 53,82,83 Generally, the reaction of dialkyl phosphonic acid esters with TMSBr affords trimethylsilyl (TMS) diesters in high yields under mild conditions.…”

“…In these mononuclear species, phen moieties are coordinated to copper centres by two nitrogen atoms and a rapid exchange of Pphen ligands is highly probable. 65 For example, line broadening in the room temperature 1 H NMR spectrum of complex 1b could be caused by the ligand exchange (Fig. S16 †).…”

“…To check this hypothesis, kinetically more stable 65 homoleptic complexes 4b and 5b were graed onto the TiO 2 surface ( Table 2). As evidenced by Cu : Ti, Cu : P, and Cu : N molar ratios obtained for these materials (Table S6 †), the immobilization was successful in both cases.…”

“…Phenanthrolinylphosphonates 6a, 7a and 9a, 64 heteroleptic copper(I) complexes Cu(Pphen)(PPh 3 )Br (1a-3a) 65 and the homoleptic complex [Cu(Pphen) 2 ]PF 6 (4a) 65 were obtained according to our previous reports.…”

Contribution of I. P. Beletskaya in the Twentieth Year Successful Russian-French Cooperation in Catalytic Syntheses

“…The first comprised mixed-ligand CuI complexes with phenanthroline and triphenylphosphine, the second series included bischelates with two phenanthroline ligands, both were studied using NMR and X-Ray technique. [55] Diethoxyphosphoryl substituted 1,10-phenanthroline copper(I) complexes were tested as catalysts in the Sonogashira-type reaction, α-arylation of phosphoryl-stabilized C-H acids, C-N, C-P bond forming reactions (substitution reactions) and in the reaction of phenylacetylene and bis(pinacolato)diboron (addition reaction). The complexes demonstrated fairly high catalytic activity and in some cases their efficiency was superior to that of the parent Cu(phen)(PPh 3 )Br (phen = phenanthroline).…”