Metalloporphyrins as Initiators for Living and Immortal Polymerizations

Novel block copolymers of 2-vinylpyridine and ɛ-caprolactone: Synthesis and characterization

“…The observed resonances in the 13 C NMR spectrum agree with the chemical shifts reported in literature for the respective homopolymers 33,34) . The carbonyl group of the first CL moiety in the block copolymer could not be observed separately.…”

“…The formation of linear polymer chains is favored in apolar solvents 11) . Another way to suppress the side reactions is to initiate the polymerization with metal alkoxides 12) and aluminum porphyrins 13) . However, the synthesis of block copolymers with these types of initiators requires more than one step or involves the tedious synthesis of porphyrine initiators [14][15][16] .…”

Crystalline-gradient polycarbonates prepared from enantioselective terpolymerization of meso-epoxides with CO2

“…Although the M n 's are lower than the expected values, a linear relationship between the conversion of epoxide and M n of the resultant copolymers was found, which was consistent with the immortal polymerization characteristic (Fig. 6, plots-(c) and (d)) 35 . However, it is worth noting here that the adventurous water or the addition of a protic agent such as methanol can cause chain transfer, thus resulting in the reduced molecular weight.…”

Copper- and copper– N -heterocyclic carbene-catalyzed C─H activating carboxylation of terminal alkynes with CO 2 at ambient conditions

“…Carbon dioxide is an attractive C1 building block in organic synthesis because it is an abundant, renewable carbon source and an environmentally friendly chemical reagent (8)(9)(10)(11)(12)(13). The utilization, as opposed to the storage of CO 2 , is indeed more attractive especially if the conversion process to useful bulk products is an economical one.…”

“…The utilization, as opposed to the storage of CO 2 , is indeed more attractive especially if the conversion process to useful bulk products is an economical one. Significant efforts have been devoted toward exploring technologies for CO 2 transformation, whereby harsh and severe reaction conditions are one of the major limitations for their practical applications (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15). Therefore, the development of efficient catalyst systems for CO 2 utilization under mild conditions is highly desired, especially for real world applications.…”