The syntheses and characterisation of, and the determination of 1J(103Rh–103Rh) in [(η5-C5Me5)2Rh2(µ-CH2)2{µ-CH2CR(CH2CRCH2)CH2}](R = H or Me) and [(η5-C5Me5)2Rh2(µ-CH2)2{µ-Ph2P(CH2)nPPh2}]2+(n= 1 or 2)

Abstract

Reaction of [(η⁵-C₅Me₅)₂Rh₂(µ-CH₂)₂Cl₂] with CH₂CRCH₂MgCl gave [(η⁵-C₅Me₅)₂Rh₂(µ-CH₂)₂{µ-CH₂CR(CH₂CRCH₂)CH₂}](3, R = H; 4, R = Me). Reaction of [(η⁵-C₅Me₅)₂Rh₂(µ-CH₂)₂(MeCN)₂]²⁺ with Ph₂P(CH₂)_nPPh₂gave [(η⁵-C₅Me₅)₂Rh₂(µ-CH₂)₂{µ- Ph₂P(CH₂)_nPPh₂}]²⁺(5, n= 1; 6, n= 2). The complexes (3)–(6) were characterised largely by their n.m.r. spectra which also allowed the determination of ¹J(¹⁰³Rh–¹⁰³Rh) as 13.5 for (3), 13.2 for (4), 12.4 for (5), and 11.9 Hz for (6). After allowance for gyromagnetic ratios and s-electron densities at the nuclei, these coupling constants are comparable with a ¹J(^l95Pt–¹⁹⁵Pt) coupling of ca. 8 000 Hz.