Synthesis, characterization and structure of ferrocenylketimine complexes of platinum(II)

Access to Planar Chirality through Cycloplatination of ((Dimethylamino)methyl)ferrocene by cis-[PtCl2(SOMeAr)2] (Ar = Phenyl, p-Tolyl)

“…(iv) The fact that the p -tolyl ring is directed at the C 5 H 5 group, providing an H(10)···C(19) distance of 2.939 Å (a sum of the van der Waals radii) in 4 , accounts for a 20° staggered conformation of the Cp rings. The opposite orientation of the phenyl ring in 3 is accompanied by an eclipsed configuration, as observed for other cycloplatinated ferrocene derivatives. ,− The platinum center has a square-planar environment. The bond lengths and angles in molecules 3 and 4 are in the same range as recently reported. ,− The Pt−C bond distances equal 1.990(4) and 1.975(8) Å, and the Pt−Cl bond distances are 2.4061(9) and 2.395(2) Å for 3 and 4 , respectively.…”

“…In addition to the recently emphasized virtue of planar chiral ferrocenes in various fields of chemistry, studies in this area are undoubtedly a great challenge. The recent progress in using the platinum(II) complex cis -[PtCl 2 (dmso) 2 ] as a cyclometalating agent for sp 2 C−H bonds − suggested a synthetic approach to asymmetrically cycloplatinated ferrocenes using Pt II coordinated to enantiomerically pure sulfoxides of the type SOMeAr. The fact that the sulfoxide remains bound to Pt II in the reaction product, unlike amino acid derivatives used as asymmetric inductors by Sokolov, gave hope for their utility in asymmetric cycloplatination and/or subsequent resolution of the planar chiral species formed.…”

Abnormal cyclopalladation of Schiff bases made of metallocenyl aldehydes and α-ferrocenylethylamine: Unexpected formation of the heteroannular 3-atomic bridge

“…Recently many publications have appeared devoted to organometallic derivatives of Schiff bases (aldimines and ketimines) in ferrocenyl series [1][2][3][4][5][6]. Synthetic approaches have been elaborated such as direct mercuration [1,2], cyclopalladation [3,4], cycloplatination [5] as well as transmetalation [6].…”

“…Synthetic approaches have been elaborated such as direct mercuration [1,2], cyclopalladation [3,4], cycloplatination [5] as well as transmetalation [6]. Azomethines derived from a-carbonyl derivatives of ferrocene and primary amines, mostly arylamines, served as models for cyclopalladation, and regioselectivity of the reaction was demonstrated since palladium atom enters into position 2 of the cyclopentadienyl ring of metallocene exclusively, in spite of the presence of aryl group which might form stable five-or six-membered chelated palladacycle.…”

Diarylplatinum(II) Compounds as Versatile Metallating Agents in the Synthesis of Cyclometallated Platinum Compounds with N-Donor Ligands

“…In contrast to cyclopalladation reactions for which Pd(OAc) 2 is a very useful precursor leading to formation of a wide variety of palladacycles [18,19], an analogous "universal" starting material is unknown for cycloplatination reactions. Recent reports on cycloplatination reactions proved that cis-[PtCl 2 (dmso) 2 ] is a reasonable metallating agent leading to higher yields and cleaner reactions than the more classical OPEN ACCESS K 2 [PtCl 4 ] starting material [20][21][22][23][24][25][26][27][28][29][30]. In these systems, the labile sulfoxide ligands are easily replaced for nitrogen atoms, thus affording the required initial coordination of the nitrogen-donor ligand, which is followed by ortho-metallation.…”