Abstract
A series of dialkyl phenylphosphines and their analogous aniline substrates have been metallated with the synergistic mixedmetal base [(TMEDA)Na(TMP)(CH2SiMe3)Mg(TMP)] 1. Different metallation regioselectivities for the substrates were observed, with predominately lateral or meta-magnesiated products isolated from solution. Three novel heterobimetallic complexes [(TMEDA)Na(TMP)(CH2PCH3Ph)Mg(TMP)] 2, [(TMEDA)Na(TMP)(m- C6H4PiPr2)Mg(TMP)] 3 and [(TMEDA)Na(TMP)(m- C6H4NEt2)Mg(TMP)] 4 and two homometallic complexes [{(TMEDA)Na(EtNC6H5)}2] 5 and [(TMEDA)Na2(TMP)(C6H5PEt)]2 6 derived from homometallic metalation have been crystallographically characterised. Complex 6 is an unprecedented sodium-amide, sodium-phosphide hybrid with a rare (NaNNaP)2 ladder motif. These products reveal contrasting heterobimetallic deprotonation with homometallic induced ethene elimination reactivity. Solution studies of metallation mixtures and electrophilic iodine quenching reactions confirmed the metallation sites. In an attempt to rationalise the regioselectivity of the magnesiation reactions the C-H acidities of the six substrates were determined in THF solution using DFT calculations employing the M06-2X functional and cc-pVTZ Dunning’s basis set.
Original language | English |
---|---|
Pages (from-to) | 15669-15677 |
Number of pages | 8 |
Journal | Chemistry - A European Journal |
Volume | 24 |
Issue number | 58 |
Early online date | 12 Aug 2018 |
DOIs | |
Publication status | Published - 17 Oct 2018 |
Keywords
- organic molecules
- organo-alkali chemistry
- ortho-metallation
Fingerprint Dive into the research topics of 'Contrasting synergistic heterobimetallic (Na-Mg) and homometallic (Na or Mg) bases in metalation reactions of dialkylphenylphosphines and dialkylanilines: lateral vs ring selectivities'. Together they form a unique fingerprint.
Prizes
-
Humboldt Research Award: One of Germany's most prestigious prizes for an international scholar
Mulvey, Robert (Recipient), 2018
Prize: Prize (including medals and awards)