Protophane und Polyaromaten, XXII. Nucleophile Alkylierung und Arylierung des 2,2′‐Bipyridyls

Abstract

2,T-Bipyridyl konnte erstmals nucleophil alkyliert werden. Bei der Umsetzung mit Methyl-und n-Butyllithium entstand je nach den Bedingungen sehr selektiv die 6-Alkyl-oder 6,6-Dialkyl-Verbindung (41 -64 %). Die Anwendung relativ tiefer Temperaturen erlaubte in mittlerer Ausbeute auch die Darstellung von CAryl-Verbindungen (Aryl = Phenyl, 2-Pyridyl). Im Konkurrenzversuch zeigte 2,T-Bipyridyl gegeniiber n-Butyllithium deutlich hohere elektrophile Aktivitat als Pyridin. Protophanes and Polyaromatics, XXII"Nucleophilic Alkylation and Arylation of 2,2'-Bipyridyl 2,Z'-Bipyridyl was alkylated by nucleophilic substitution for the first time. The reaction with methylor n-butyllithium yielded very selectively either the 6-alkyl-or the 6,6'-dialkyl compound (41 -64 %) depending on the conditions. Applying relatively low temperatures it was possible to prepare 6-aryl-2,2-bipyridyIs (aryl = phenyl, 2-pyridyl) in medium yields. In a competition experiment with n-butyllithium 2,2'-bipyridyl was significantly more electrophilic than pyridine.Ziegler und Zeiser 1 ') XXI.

Dinuclear, Tricyclometallated Platinum(II) Derivatives − Substitution Reactions and Reactivity of the Platinum−Carbon Bonds

“…The mass spectrometric measurements were performed with a VG 7070EQ instrument, equipped with a PDP 11-250J data system and operating under positive ion fast atom bombardment (FAB) conditions with 3-nitrobenzyl alcohol as supporting matrix. cis-[Pt(Me) 2 (DMSO) 2 ] and cis-[Pt(Ph) 2 (DMSO) 2 ] were prepared according to literature procedures, [13] as were the ligand HL [14] and complexes 1a and 1b. [7] [Pt 2 (Me)(L)(PPh 3 ) 2 ] (2a): PPh 3 (84.9 mg, 0.324 mmol) was added, under vigorous stirring, to a solution of 1a (125.0 mg, 0.158 mmol) in CH 2 Cl 2 (15 mL).…”

The sensitivity of the lehn cryptand—europium and terbium (III) complexes to anions compared to a coordinatively saturated systems

“…[ 6-Bromomethyl-2,2 0 -bipyridine 10. 6-Methyl-2,2 0 -bipyridine was prepared according to the procedure of Kauffman [20] from 2,2 0 -bipyridine and methyllithium. The product had m.p.…”

Neutral and Cationic Methyl Complexes of Platinum(II) with 6-Substituted 2,2′-Bipyridines: Synthesis, Characterisation and Reactivity with Carbon Monoxide − Molecular Structures of [PtCl(methyl)(6-ethyl-2,2′-bipyridine)] and of [Pt(methyl)(acetonitrile)(6-ethyl-2,2′-bipyridine)][BF4]

“…General: The unsymmetric 6-R-2,2Ј-bipyridine HL 3Ϫ7 ligands were obtained through not trivial syntheses according to a procedure previously described, [20] the ligand HL 2 according to Kauffmann et al [21] The compounds trans-[PtCl(Me)(SMe 2 ) 2 ], [22] trans-[PtI(-Me)(SMe 2 ) 2 ] [22] and Na[BArЈ 4 ] [23] {sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate} were prepared as reported elsewhere. All solvents were freshly distilled prior to use.…”