David A. Robson

THYMINE FUNCTIONALISED POLYMERS VIA LIVING RING-OPENING METATHESIS POLYMERISATION

Thymine functionalised poly(norbornene)s are synthesised via nliving ring-opening metathesis polymerisation using the ruthenium ninitiator n{RuCl n 2 n(CHPh)[P(C n 6 nH n 11 n) n 3 n] n n 2 n}.

Ring opening metathesis polymerization of 2,3-diazanorborn-5-ene derivatives

The synthesis and polymerisation of 2,3-diazanorborn-5-enes are reported. Reaction of 2,3-diazanorborn-5-ene derivatives 6–9 with molybdenum based initiators 1–3 leads, in most cases to ring opening metathesis polymerization. By contrast, monomers 6–9 are not polymerized by ruthenium based initiator 4. The polymers were characterized by NMR, GPC and MALDI-TOF mass spectrometry and were found to have narrow molecular weight distributions and to show a resonance attributable to a propagating alkylidene in the 1H NMR spectrum.

The synthesis and ring-opening metathesis polymerization of peptide functionalized norbornenes

Norbornene monomers bearing two and three amino acid residues have been synthesized and the ring-opening metathesis polymerization of the monomers investigated using Mo(CHCMe2Ph)(N-2,6-Pri2C6H3)(OR)2, [R = CMe3 1a, CMe2CF3 1b, CMe(CF3)2 1c].

Synthesis of nucleic-acid base containing norbornene derivatives as monomers for ring-opening-metathesis-polymerization

A series of norbornene derivatives containing nucleic-acid bases (thymine, adenine, cytosine, guanine, or uracil) have been prepared as monomers for ring-opening-metathesis–polymerization (ROMP). Many of the initially prepared monomers had poor solubility but this could be overcome by appropriate choice of a linker between the norbornene and base units. Some of the monomers were successfully polymerised to give homopolymers derived from nucleic-acid bases.

An unprecedented coordination mode for hemilabile pendant-arm 1,4,7-triazacyclononanes and the synthesis of cationic organoaluminium complexes

Reaction of AlMe3 or [AlMe3·py] nwith the pendant arm OH-funtionalised 1,4,7-triazacyclononane proligands, nHL1 or HL2, affords the four- and five-coordinate nderivatives [Al(L1)Me2] 1 or n[Al2(L2)2Me4] 2 in which the npendant alkoxide O-donor and only one macrocycle N-donor is bound nto Al; methyl anion abstraction from 1 yields cationic, pentacoordinate n[Al(L1)Me]+ in which L1 has a tetradentate ncoordination mode [L1 = n1-(2-hydroxy-3,5-di-tert-butylbenzyl)-4,7-diisopropyl-1,4,7-triaz ncyclononane; L2 = 1-(2-hy- ndroxy-2-methylethyl)-4,7-diisopropyl-1,4,7-triazacyclononane].