241

We wish to report two types of new polymer-supported quaternary salts as effective and reusable catalysts for halogen-exchange fluorination of aryl chlorides with potassium fluoride (KF) in sulfolane.

Polystyrene-supported pyridinium salt 1 catalyzed the reaction of 4-chloronitrobenzene (PCNB) with KF in sulfolane at 180 °C for 5 h to give 4-fluoronitrobenzene (PFNB) in 87% yield. Without 1, only 10% yield of PFNB was obtained. Polymer 1 could be reused at least 8 times in repeat runs.

KF CIONO 2 :- F O N O 2

(PCNB) 1 or 2 (PFNB)

Br- c.3 I Z-~CH(CH2)9N k - ~ NL'] i ~ - P + - P h 3 Ol-

d e Et 1 2

Another new type of catalyst tetraphenylphosphonium salts-grafted copolymer 2, which has the advantage of being easier to prepare than 1, was tried for fluorination. Polymer 2 was also effective as a reuseable catalyst for fluorination of PCNB at 180°C.

The synthetic utility of 1 and 2 will be further demonstrated by the successful fluorination of various aryl chlorides.

Published in Tetrahedron Lett., 30 (1989) 7199; Chem. Lett., (1990) 769.

Reactive Carriers for Immobilization Maria C. Walenius and Per Flodin, Department of Polymer Technology, Kemig&rden 3, Chalmers University of Technology, S-412 96 Gi~teborg, Sweden

Macroporous functionalized gels based on trimethylolpropane trimethacrylate (TRIM) and glycidyl methacrylate (GMA) have been prepared for the immobilization of metal ions, e.g., Cu(II), Fe(III) and Ni(II).

The gels were functionalized by iminodiacetate (IDA) and aliphatic or cyclic polyamines. The coordination properties of these chelating ligands have been investigated by elementary analysis and the adsorption of metal ions. The selectivity of the metal ions depended on the structure of the chelating ligand. The soft and intermediate metal ions preferred amine and amino nitrogen as coordination atoms whereas hard metal ions preferred carboxyl oxygen.

The matrix was mechanically stable even at rather high concentrations of GMA (about 38-50 mol%). This makes gels of poly(TRIM-co-GMA) more advantageous than conventional gels. The adsorption of metal ions was quite high for some chelating ligands.

These gels can be applied in waste water treatment or for affinity chromatography of peptides and proteins [1].

1 J. Porath and B. Olin, Biochemistry, 22 (1983) 1621.

To be published in React. Polyn~

An Organic-Inorganic Hybrid Polymer Derived from Polyoxazoline S. Kure, Y. Chujo and T. Saegusa, Department of Synthetic Chemistry, Faculty of Engineering, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606, Japan

Ring-opening polymerization of 2-oxazolines produces polyoxazoline (POZO) having an oxazolinium propagating end, which reacts with various nucleophiles such as amines. As a novel silane coupling agent, triethoxysilyl-terminated POZO was synthesized by the treatment of the oxazolinium end group with 3-aminopropyltriethoxysilane (Scheme 1).

242

Scheme I ell3 .,.,~ O .CH3 ~1 ~ CH3

L___/ Or;

CH 3 .,,,~O 1) H 2 N ~ S i ( O E t ) 3 ,.~1~1 ~ 2) ion exchange resin " CH3 N / ~ / ~ S i ( O E t ) 3 1 '"H

As illustrated in Scheme II, acid-catalyzed cohydrolysis of triethoxysilyl-terminated POZO and tetraethoxysilane (sol-gel method) produced POZO-modified silica gel which was homogeneous and transparent. This homogeneity might be due to the interaction between the amide group in POZO and silica. In other words, the molecular level combination between organic polymer (POZO) and inorganic polymer (silica) has been accomplished, for which the name "Organic-Inorganic Hybrid Polymer" has been proposed. This hybrid was found to show high water adsorption due to the hydrophilic POZO segments.

Scheme II 1_ + Si(OEt)4

On the other hand, the pyrolysis of the present hybrid at 600°C eliminated the organic segments (POZO) to produce a porous silica. For example, a porous silica with 0.5 cc /g pore volume and 800 m2/g surface area was produced by this procedure. These values of pore volume and surface area could be controlled by the feed ratio of POZO and tetraethoxysilane.

P h o t o c h e m i s t r y o f P y r i m i d i n e C o n t a i n i n g P o l y m e r s

Y o s h i a k i I n a k i a n d K i i c h i T a k e m o t o , Department of Appfied Fine Chemistry, Faculty of Engineer- ing, Osaka University, Suita, Osaka 565, Japan

It is well known that pyrimidine bases convert ot photodimers upon irradiation by UV light near 270 nm. This photochemical reaction has a lethal effect in biological systems due to the photochemical transformation of pyrimidine bases of nucleic acids. However, the photodimerization is a reversible reaction and the photodimers split to afford the original monomers very efficiently upon irradiation at a shorter wavelengths as shown in Scheme 1.

o o o H ~ /CH 3 H l[ Me Me [I H

2 5 0 nm I I R R R

Scheme 1

Pyrirnidine derivatives were found to be applicable to both negative and positive type deep-UV photoresists [1-4]. Intermolecular photodimerization of pyrimidine bases in the side chain of various polymeric and dirneric compounds upon irradiation with UV light (270 nm) led to the photocrosslinking of the polymer chains or photopolymerization of the dimeric compounds. This in turn allows the use of these materials as deep-UV negative type photoresists. Photolithographic evaluation of a typical polymer showed very high sensitivity with good resolution. Polymethacry- lates containing 6-cyanouracil or 5-bromouracil units in the side chain of the polymer displayed the highest photosensitivity. Copolymers of butadiene with the methacrylate monomer with pendant 6-cyanouraeil are capable of resolving 0.5/~g features and behaved as negative photoresists.