74708-16-0Relevant articles and documents
RECYCLABLE POLYMERS BASED ON RING-FUSED GAMMA-BUTYROLACTONES
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Page/Page column 34; 42, (2020/02/23)
The invention discloses a class of new polymers, trans-ring-fused poly(4-hydroxybutyrate)s (RF-P4HB) that exhibit a unique set of properties, including robust thermal stability and mechanical strength, quantitative recyclability to the building block monomers via thermolysis and/or chemical catalysis, and convenient production from the chemical ring-opening polymerization under ambient temperature and pressure. Another unique property is the formation of crystalline stereocomplexed polymers with high melting temperature upon mixing the two enantiomeric RF-P4HB chains via stereocomplexing co-crystallization. This invention also provides the corresponding ring-fused lactone monomer structures that enable the synthesis of the RF-P4HB polymers, through trans-fusing of rings to the parent γ-butyrolactone ring. Furthermore, a polymerization or copolymerization process for the synthesis of RF-P4HB polymers and copolymers is disclosed.
Efficient Oxidative Cleavage of Tetrahydrofuran-2-methanols to γ-Lactones by a 2-Iodobenzamide Catalyst in Combination with Oxone
Yakura, Takayuki,Horiuchi, Yuto,Nishimura, Yushi,Yamada, Akihiro,Nambu, Hisanori,Fujiwara, Tomoya
supporting information, p. 869 - 873 (2016/04/05)
An environmentally friendly oxidative cleavage of tetrahydrofuran-2-methanols to the corresponding γ-lactones using a catalytic amount of 2-iodo-N-isopropylbenzamide has been developed. The reaction of various tetrahydrofuran-2-methanols with the catalyst in the presence of Oxone (2 KHSO5·KHSO4·K2SO4) as a co-oxidant in DMF at room temperature successfully affords the corresponding lactones in good to high yields, and recovery of the catalyst is readily accomplished using a reductive work-up. This method is notable because it enables the transformation of tetrahydrofuran-2-methanols to γ-lactones under mild conditions without the use of any toxic heavy metals.
On the stereochemical course of the addition of allylsilanes to aldehydes
Denmark, Scott E.,Weber, Eric J.,Almstead, Neil G.,Wolf, Larry M.
experimental part, p. 7701 - 7718 (2012/09/11)
Model compounds 3 and 5 have been studied to determine the orientation of the reacting double bonds in the transition state of the allylmetal-aldehyde addition. These models were designed to remove any intrinsic steric bias for the formation of the bicyclic products that would obfuscate a stereoelectronic contribution to the transition states. Model system 3 revealed a modest preference for the synclinal transition state, albeit in very low yields. Model system 5 underwent selective and largely Lewis acid independent cyclization primarily via a synclinal transition state. The high proximal selectivity observed in these cyclizations likely reflects the selectivity of an unhindered allylmetal-aldehyde addition for the synclinal transition state and results from a stereoelectronic preference, not an intrinsic steric bias, for the synclinal arrangement of double bonds.
