TY - JOUR
T1 - Inductive effect-assisted chain-growth polycondensation. Synthetic development from para- to meta-substituted aromatic polyamides with low polydispersities
AU - Sugi, Ryuji
AU - Yokoyama, Akihiro
AU - Furuyama, Taniyuki
AU - Uchiyama, Masanobu
AU - Yokozawa, Tsutomu
PY - 2005/7/27
Y1 - 2005/7/27
N2 - The polycondensation of m-(octylamino)benzoic acid esters (1) with base was investigated in order to extend the synthesis of well-defined condensation polymers from para-substituted polymers to meta-substituted ones. We expected that the aminyl anion of 2 would deactivate the ester moiety at the meta position of 2 owing to the strong inductive effect of the anion, resulting in, not self-polycondensation, but chain-growth polycondensation. The methyl ester monomer 1a polymerized with lithium hexamethyldisilazide (LiHMDS) in the presence of phenyl benzoate (3a) as an initiator at 0 °C to afford a polymer with a low polydispersity, but the product contained a small amount of self-condensation polymer. On the other hand, the polymerization of the ethyl ester monomer (1b) with phenyl 4-methylbenzoate (3b) proceeded through chain polymerization without self-polycondensation. The M n values of the polymers increased linearly in proportion to the [1b] 0/[3b] 0 ratio, and the M w/M n ratios remained narrow over the entire [1b] 0/[3b] 0 range. Furthermore, a block copolymer of N-alkylated poly(m-benzamide) and poly(p-benzamide) with a low polydispersity was synthesized by the monomer addition method under this polymerization condition.
AB - The polycondensation of m-(octylamino)benzoic acid esters (1) with base was investigated in order to extend the synthesis of well-defined condensation polymers from para-substituted polymers to meta-substituted ones. We expected that the aminyl anion of 2 would deactivate the ester moiety at the meta position of 2 owing to the strong inductive effect of the anion, resulting in, not self-polycondensation, but chain-growth polycondensation. The methyl ester monomer 1a polymerized with lithium hexamethyldisilazide (LiHMDS) in the presence of phenyl benzoate (3a) as an initiator at 0 °C to afford a polymer with a low polydispersity, but the product contained a small amount of self-condensation polymer. On the other hand, the polymerization of the ethyl ester monomer (1b) with phenyl 4-methylbenzoate (3b) proceeded through chain polymerization without self-polycondensation. The M n values of the polymers increased linearly in proportion to the [1b] 0/[3b] 0 ratio, and the M w/M n ratios remained narrow over the entire [1b] 0/[3b] 0 range. Furthermore, a block copolymer of N-alkylated poly(m-benzamide) and poly(p-benzamide) with a low polydispersity was synthesized by the monomer addition method under this polymerization condition.
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U2 - 10.1021/ja052566z
DO - 10.1021/ja052566z
M3 - Article
C2 - 16028920
AN - SCOPUS:22944460478
VL - 127
SP - 10172
EP - 10173
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
SN - 0002-7863
IS - 29
ER -