Electric Literature of 1806-29-7. Let’s face it, organic chemistry can seem difficult to learn. Especially from a beginner’s point of view. Like 1806-29-7, Name is 2,2-Biphenol. In a document type is Article, introducing its new discovery.
Spirocyclic phenoxides of germanium, zirconium, and tin were prepared from 2,2?-dihydroxybiphenyl and 2,2?-dihydroxy-1,1?-binaphthyl. Ring-expansion polymerizations of l-lactide are mainly studied at 160 or 180 C. The reactivity of the catalysts increases in the order: Zr < Ge < Sn. Regardless of catalyst, the weight-average molecular weights (Mw) never exceed 50,000 g mol?1. The resulting poly(l-lactide)s are optically pure and have a cyclic architecture. Decreasing temperature and time favor formation of even-numbered cycles, and at 102 cyclics, almost free of odd-numbered rings are obtained. Analogous polymerizations of meso-lactide give similar results >120 C, but different results at 100 or 80 C. Surprisingly, bell-shaped narrow molecular weight distributions are obtained <140 C, resembling the pattern of living polymerizations found for alcohol-initiated polymerizations. An unusual transesterification mechanism yielding narrow distributions of odd-numbered cycles is discovered too. If you are interested in 1806-29-7, you can contact me at any time and look forward to more communication.Electric Literature of 1806-29-7