Organoborane initiators

Structural plastic adhesive (3M, Dow, Loctite) Amine-complexed organoborane initiator, methyl methacrylate or high-molecular-weight monomer and elastomer Most are flammable/ volatile and very slow fixture. Good adhesion to a wide range of materials including polyolefins and tough, environmentally resistant bonds. 

I. 13. In this example, with a postpolymerization modihcation of a polyhomologated organoborane, initiator/catalyst BEt3 produces three-arm polymethylene architectures with well-controlled molecular weight and low PDI. These materials are not readily available by conventional ethylene polymerization. 

Structurally novel borane initiators can also provide access to well-defined polymethylene architectures. For example, polycyclic organoborane initiators offer an opportunity for the construction of tube-like macrotricyclic organoboranes. These structures may be elaborated to hydrocarbon star polymer structures following the oxidative cleavage of the... 

Organoborane-Initiated Polymerization of Allyhc Arsonium Ylides. 225... 

Similarly, cyclopropyl-substituted ylide 14 was prepared and subjected to organoborane-initiated polymerization [68]. Although 14 again cannot be ho-mopolymerized for steric reasons in a similar manner as 13, copolymerization of... 

On the other hand, because TDM and dimethylsulfoxonium methylide 11 react with organoborane in a similar mechanism (formation of borate followed by 1,2-migration), organoborane-initiated copolymerization of TMD with 11 proceeded to give poly(TMSmethylidene-co-methylene), which is a partially TMS-substituted polymethylene [69]. Although the composition of TMSCH in the products was lower than that expected from the feed ratio of [TDM]/[11], oligomers with a relatively narrow MWD were obtained as shown in Scheme 47. 

Organoborane-Initiated Polymerization of Allylic Arsonium Ylides... 

In 2005, Gall, Mioskowski, and coworkers reported the organoborane-initiated polymerization of allylic arsonium ylides, which proceeds in a mechanism closely related to that of 11 [76]. However, in this process the polymer main chain is not constructed from one carbon unit but three carbon unit, which results in the formation of a series of poly(2-substimted-l-propenylene)s. When 2-substituted allylic arsonium ylide generated by the reaction of the corresponding arsonium salt with base... 

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