The CO2 insertion into Sn−O bonds of a series of butyl(phenoxy)-, (alkoxy)-, and (oxo)stannanes has been investigated. The tributyl derivatives Bu3SnOR (2a, R = Me; 3a, R = iPr; 4a, R = tBu; 5a, R = SnBu3)1 give quantitatively Bu3Sn(OCO2R), 2b−5b; the analogous tributylphenoxystannane, 1, is less reactive. For the dibutyl series, Bu2Sn(OR)2, steric effects of tBu groups in OR (8a) suppress carbonation under atmospheric pressure. With R = Me (6a) or R = iPr (7a), only one Sn−OR bond reacts, resulting in Bu2Sn(OR)(OCO2R), 6b or 7b. Treating 6a with 2-propanol affords under CO2 the mixed compound Bu2Sn(OMe)(OCO2 iPr), selectively. Facile deinsertion of CO2 is a common property of all compounds, occurring more readily in the dibutyl series. The stoichiometric transformation of the carbonato ligand in 2b, 5b, or 6b to dimethyl carbonate (DMC) on reaction with MeI requires nucleophilic assistance by F- to proceed. In the presence of MeOH, 2b and 5b are almost inactive forDMC formation, in contrast with 6b. The best yield is obtained under supercritical CO2−methanol conditions.

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The first continuous, biphasic, Pd-catalysed dimerisation of methylacrylate is described. The biphasic system has been realised by using a tetrafluoroborate ionic liquid as catalyst medium and an ammoniumphosphine ligand to immobilise and stabilise the Pd-catalyst.

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The η6‐1,3,5‐triphosphabenzene transition metal complexes 12a,b, 14, and 16 have been synthesized for the first time by the displacement of η6‐arene ligands (toluene, benzene and naphthalene) with 2,4,6‐tri‐tert‐butyl‐1,3,5‐triphosphabenzene (9). The new complexes have been fully characterized by a combination of elemental analysis, mass spectrometry, and 1H‐, 13C‐ and 31 P‐NMR spectroscopy.