Well‐defined poly(alcohol)s were prepared directly by the living coordination polymerization of allene derivatives bearing hydroxy groups with [{(π‐allyl)NiOCOCF3}2]/PPh3 as an initiator (see scheme). R=CH2OH, CHCH3OH, C(CH3)2OH.

A living block copolymerization of allene derivatives with 1‐phenylethyl isocyanide (3) using [(allyl)NiOCOCF3]2 (1) is described. After complete polymerization of allene monomers such as n‐octyloxyallene (2A) with 1, further addition of 3 to the reaction system yielded the corresponding block copolymers in high yield. For instance, a block copolymer (4A, Mn = 39,600, Mw/Mn = 1.20) was obtained in 96% yield by the addition of 3 ([3]/[1] = 250) to the living solution of poly(n‐octyloxyallene) (Mn = 14,400, Mw/Mn = 1.03) prepared by the polymerization of 2A in the ratio of [2A]/[1] = 90. The resulting copolymer was a brownish orange gum or a solid, depending on the length of each of the segments. The solubility of the block copolymers could be controlled by the allene components. The copolymer of 2A with 3 having appropriate length of segments was soluble in n‐hexane, while that of methoxyethoxyethoxyallene (2D) with 3 was soluble in methanol. © 1997 John Wiley & Sons, Inc.

The allylnickel-catalyzed living coordination polymerization of allene derivatives was carried out in protic solvents such as EtOH to figure out their effect on the polymerization behavior. For example, the coordination polymerization of methoxyallene (2a) by [(allyl)NiOCOCF3]2 (1)/PPh3 in EtOH proved to proceed in a living fashion giving a narrowly dispersed polymer in a high yield. In this case, a remarkable acceleration of the polymerization and the higher selectivity of the 1,2-polymerization were observed compared to the case of the polymerization in aprotic solvents such as toluene. That is, the polymerization of 2a (50 equiv, [2a]0 = 1.0 M) was complete within 2 h in EtOH to give a polymer in 95% yield (M n = 4400, M w/M n = 1.10, 1,2-:2,3-polymerizations = 63:37), while it required 12 h in toluene to obtain a polymer having higher content of the 2,3-polymerized unit in a 99% yield (M n = 4100, M w/M n = 1.07, 1,2-:2,3-polymerizations = 27:73). In protic solvents, the actual propagating species was supposed to be a cationic π-allylnickel complex on the basis of its 1H NMR and 19F NMR spectra. The use of protic sources such as pyrrole, indole, and phenol was also found to be effective to accelerate the polymerization and to increase the 1,2-polymerization selectivity.

An end‐π‐allylnickel macroinitiator (3) was prepared by the reaction of poly(ethylene glycol) allenyl methyl ether with an excess amount (5 equiv) of [(π‐allyl)NiOCOCF3]2 (1) in the presence of PPh3 ([PPh3]/[1] = 1). The resulting macroinitiator was used as an initiator for the polymerization of 1‐phenylethyl isonitrile (4a) to give a block copolymer [poly(ethylene glycol)‐block‐poly(4a)]. The molecular weight and composition of the block copolymers were controlled by the molecular weight of 3 and the ratio of 4a to 3. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 495–499, 2001

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