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Studies on polymeric reagents. I. Synthesis of dichocrocis punctiferalis guenuée, trans-10-hexadecene-1-al, using a polymeric reagent
335
0
NcaOH,PTC c on d'~.
©
cH2c, (1) X=O t - O H (2) X=S
L'OH
~.-OH (3)
~OH
Polymer-supported diols 1 and and 2 have been used as protecting groups for aldehydes and ketones. We wish to report the preparation of polymer-supported hydroxythiol 3 by the reaction shown. Polymer 3 was prepared with a capacity of up to 2.5 mmol/g. Several dialdehydes and diketones were bound to polymer 3 in loadings of 0.3-1.7 mmol/g. SH ÷ ON
O=c/PTSA'N%S04 \ ( N +, wet dioxan
(~-S~C/+
1-120
t--O
Various reactions, including Wittig reactions, were carried out on the free carbonyl groups of singly bound dicarbonyl compounds. After release from the polymer the ratio of Wittig product to starting material indicated that terephthaldehyde was 70% single bound and 30% doubly bound. These results are similar to those obtained for polymer-supported acetals and ketals by other workers.
Studies on Polymeric Reagents. I. Synthesis of Dichocrocis Punctiferalis Guenu6e, trans-lOHexadecene-l-al, Using a Polymeric Reagent C h e n H i a w e i , J i a n g J i l o n g a n d W u Y i n q i u , Hubei University, Wuhan, People~' Republic of China
cis-lO-Hexadecene-l-ol was synthesized from polymer-bonded Wittig reagent. The sodium salt of Me2SO in Me2SO was used as base. Then, Dichocrocis Punctiferalis Guen6e, trans-lO-hexadecene-l-al, was synthesized after isomerization and oxidation. The structures of the product and intermediates were identified by IR, ]H NMR, MS and elemental analysis. The ratio of cis- to trans-lO-hexadecene-l-ol before and after isomerization was determined as well. The results indicate that the above polymeric Wittig reaction has high cis-selectivity and that the ratio of cis- to trans-product corresponds with the requirement of biological activity of the sex pheromone. To be published in Reactive Polymers.
Phase Transfer Catalyzed Chlorination of Poly(p-methylstyrene) S. M o h a n r a j
a n d W a r r e n T. F o r d , Oklahoma State University, Stillwater, OK, U.S.A.
Chlorination of the methyl groups of poly(p-methylstyrene) with aqueous sodium hypochlorite and benzyhriethylammonium chloride as catalyst provides a new route to chloromethyl-substituted aromatic polymers. Conversions of up to 20% of methyl to chloromethyl groups were achieved with no detectable formation of dichloromethyl groups. Conversion of up to 73% of methyl to chloromethyl groups occurs with 12% concomitant formation of dichloromethyl groups. The method has been applied to soluble, 1% crosslinked, and 20% crosslinked macroporous polymers. Phase transfer catalyzed chlorination of poly(p-methylstyrene) is much safer than chloromethylation of polystyrene and much less expensive than the use of chloromethylstyrene monomer for preparation of functional derivatives of polystyrene. Published in Macromolecules, 19 (1986) 2470.
0
NcaOH,PTC c on d'~.
©
cH2c, (1) X=O t - O H (2) X=S
L'OH
~.-OH (3)
~OH
Polymer-supported diols 1 and and 2 have been used as protecting groups for aldehydes and ketones. We wish to report the preparation of polymer-supported hydroxythiol 3 by the reaction shown. Polymer 3 was prepared with a capacity of up to 2.5 mmol/g. Several dialdehydes and diketones were bound to polymer 3 in loadings of 0.3-1.7 mmol/g. SH ÷ ON
O=c/PTSA'N%S04 \ ( N +, wet dioxan
(~-S~C/+
1-120
t--O
Various reactions, including Wittig reactions, were carried out on the free carbonyl groups of singly bound dicarbonyl compounds. After release from the polymer the ratio of Wittig product to starting material indicated that terephthaldehyde was 70% single bound and 30% doubly bound. These results are similar to those obtained for polymer-supported acetals and ketals by other workers.
Studies on Polymeric Reagents. I. Synthesis of Dichocrocis Punctiferalis Guenu6e, trans-lOHexadecene-l-al, Using a Polymeric Reagent C h e n H i a w e i , J i a n g J i l o n g a n d W u Y i n q i u , Hubei University, Wuhan, People~' Republic of China
cis-lO-Hexadecene-l-ol was synthesized from polymer-bonded Wittig reagent. The sodium salt of Me2SO in Me2SO was used as base. Then, Dichocrocis Punctiferalis Guen6e, trans-lO-hexadecene-l-al, was synthesized after isomerization and oxidation. The structures of the product and intermediates were identified by IR, ]H NMR, MS and elemental analysis. The ratio of cis- to trans-lO-hexadecene-l-ol before and after isomerization was determined as well. The results indicate that the above polymeric Wittig reaction has high cis-selectivity and that the ratio of cis- to trans-product corresponds with the requirement of biological activity of the sex pheromone. To be published in Reactive Polymers.
Phase Transfer Catalyzed Chlorination of Poly(p-methylstyrene) S. M o h a n r a j
a n d W a r r e n T. F o r d , Oklahoma State University, Stillwater, OK, U.S.A.
Chlorination of the methyl groups of poly(p-methylstyrene) with aqueous sodium hypochlorite and benzyhriethylammonium chloride as catalyst provides a new route to chloromethyl-substituted aromatic polymers. Conversions of up to 20% of methyl to chloromethyl groups were achieved with no detectable formation of dichloromethyl groups. Conversion of up to 73% of methyl to chloromethyl groups occurs with 12% concomitant formation of dichloromethyl groups. The method has been applied to soluble, 1% crosslinked, and 20% crosslinked macroporous polymers. Phase transfer catalyzed chlorination of poly(p-methylstyrene) is much safer than chloromethylation of polystyrene and much less expensive than the use of chloromethylstyrene monomer for preparation of functional derivatives of polystyrene. Published in Macromolecules, 19 (1986) 2470.