Butanediyl palladium II

This preparation is carried out similarly to that of(l-4-butanediyl)bis(triphenyl-phosphine)palladium(II), using 0.1 g of pSCH2(CH2 H2(tmeda) (0.36 mmole) in pentane (10 mL) and 56 mg of 2,2-bipyridine (0.36 mmole) in pentane(10 mL). The reaction product, after washing with pentane, is dissolved in acetone (3 mL), and the filtered solution is kept overnight at -25 to give 0.105 g of the title compound (91%). 

Inorganic Syntheses, Volume 22 Edited by Smith L. Holt, Jr. Cop3Tight 1983 by Inorganic Syntheses, Inc. 

Submitted by P. DIVERSI, G. INGROSSO, and A. LUCHERINI Checked by K. A. ERNERt and T. H. TULIPt 

The interest in transition-metal metallacycles has led to an intensive study of a number of such complexes from the structural and chemical point of view. In this context, the availability of metallacydopentane derivatives of the cobalt-triad metals, which are implicated in so many catalytic and stoichiometric reactions, enables one to extend the range of studies of the chemistry of this class of organometallics. 

Described here is the preparation of (cyclopentadienyl)(triphenylphosphine)-metallacyclopentanes of cobalt(III), rhodium(IIl), and iridium(III). 

PdCH2(CH2)2CH2(tmeda) + bpy — PdCH2(CH2)2CH2(bpy) + tmeda 

---

Bipyridine)(l,4-butanediyl)palladium(II) is an orange crystalline air-stable solid. It can be stored for months under dinitrogen in a refrigerator without appreciable decomposition. It is insoluble in pentane, and soluble in acetone and chloroform. Its H-NMR spectrum (60 MHz, CDCI3, 6 in ppm downfield from TMS) shows two multiplets at 1.72 and 2.25 (methylenes of the palladacyclopentane moiety) and multiplets at 7.42, 8.06, and 8.76 (bipy). 

Butanediyl)(TV, TV, TV, TV -tetramethyl-l, 2-ethanediamine)palladium(II) is a white crystalline solid, highly hygroscopic and air-sensitive, readily losing tmeda. It must be handled and stored under argon. It is moderately soluble in pentane and very soluble in benzene. The H-NMR spectrum (60 MHz,benzene-rf6,5 in ppm downfield from TMS) must be recorded immediately after the preparation of the sample, at temperatures lower than 10°. It shows a broad multiplet ranging from 0.9-1.6 (methylene protons of the palladacyclopentane moiety), and resonances at 2.2-2.3 (methyl and methylene protons of tmeda). Other chemical properties are given in the literature.3... 

Butanediyl)bis(triphenylphosphine)palladium(II) is a cream-colored crystalline compound, moderately air-stable as a solid and quite unstable in solution. It is insoluble in pentane but soluble in benzene. Its H-nmr spectrum (60 MHz, benzene-c 6, 6 in ppm downfield from IMS) shows a complex multiplet centered at 2.33 (methylene protons of the palladacyclopentane moiety) and multiplets at 6.80-7.80 (aromatic protons). 

---