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An efficient N-heterocyclic carbene catalyzed glycosylation of 2-nitrogalactals with alcohols and phenol has been developed for the first time. A wide variety of 1,2-cis-2-nitroglycosides can be obtained with good to excellent yields and high to excellent α-selectivities. [ABSTRACT FROM AUTHOR]

Polyethyleneglycol borate (PEG-BAE) toughening agents were preparedfrom the esterification reaction between boric acid and PEG and characterizedby FTIR and NMR. The effect of reaction conditions such as reactiontemperatures, reaction times, and entrainer amounts on the esterificationreaction rate was studied. Incorporation of PEG-BAE into phenolic(PF) foams leads to an improvement in the flexural and compressionstrengths, and a reduced pulverization ratio compared with pure andPEG-toughened foams. The LOI results illustrate the flame-retardingeffect of PEG-BAE is better than that of pure PEG, with LOI in therange 35.5–39.0%, and all PF foams pass UL 94 V-0 rating. Conecalorimeter results indicate that the incorporation of PEG400 increasesthe peak heat-release rate (PHRR) of PF foam by 38%, whereas PEG400-BAEresults in a slightly decreased PHRR. Moreover, thermal decompositionof pure and toughened PF foams was investigated. [ABSTRACT FROM AUTHOR]