CAS: 13076-17-0; (3R,6R)-3,6-Dimethyl-1,4-Dioxane-2,5-Dione

相似化合物

95-96-5 4511-42-6 57321-93-4

上下游产品

L-丙交酯 L,L-Dilactide 4511-42-6
(3R,6S)-3,6-Dimethyl-1,4-Dioxane-2,5-Dione 13076-19-2

(3R,6S)-3,6-Dimethyl-1,4-Dioxane-2,5-Dione置于potassium Phosphate,1,8-二氮杂双环[5.4.0]十一碳-7-烯体系中,用 乙酸乙酯,甲苯 用作溶剂,化学反应 220.0H,反应生成(3R,6R)-3,6-二甲基-1,4-二恶烷-2,5-二酮
参考文献:Studies On The Epimerization Of Diastereomeric Lactides
标题:Studies On The Epimerization Of Diastereomeric Lactides
摘要:The Epimerization Of Chiral Lactides Was Studied In The Presence Of Various Homogeneous And Heterogeneous Bases. Some Solvent/base Systems Were Found To Promote Epimerization At Room Temperature Efficiently. Side Reactions Such As Polymerization Were Not Observed Or occurred Only Slowly. This New Protocol Offers The Opportunity Of The Transformation Of Meso-Lactide Into Rac-Lactide. Therefore It Can Reduce The Overall Manufacturing Costs Of Polylactides,A Problem Which Currently Hampers The Broad Application Of Those Environmentally Friendly Polymers In A Large Scale. (C) 2011 Published By Elsevier Ltd.
Doi:10.1016/j.Tetlet.2010.12.094

专利信息

专利号:US-6316590-B1
优先权日:1999-11-10
标 题 :Synthesis of stereospecific and atactic poly(lactic acid)s
发明人：COATES GEOFFREY W; CHENG MING; CHAMBERLAIN BRADLEY M
权利人:CORNELL RES FOUNDATION INC
摘要:Isotactic poly ((R)-lactic acid) or isotactic poly (S)-lactic acid are respectively prepared from (R,R)-lactide and (S,S)-lactide using a catalyst which has a zinc center or a magnesium center and two ligands where one of the ligands is a propagating group and the other of the ligands is not a propagating group. Heterotactic poly(lactic acid) is prepared from rac-lactide using a catalyst which has a zinc center and two ligands where one of the ligands is a propagating group and the other of the ligands is not a propagating group; heterotactic poly(lactic acid) is a novel composition. The catalyst with a magnesium center is a novel catalyst. Syndiotactic poly(lactic acid) is prepared from meso-lactide using a syndiotactic poly(lactic acid) effecting catalyst which has a zinc center and two ligands where one of the ligands is a propagating group and the other of the ligands is not a propagating group and the preferred catalyst contains as the ligand which is not a propagating group diiminate substituted with isopropyl substituted phenyl and the propagating group is isopropoxide. Atactic poly(lactic acid) of polydispersity ranging from 1.15 to 1.40 is prepared in less than 10 minutes by polymerizing rac-lactide in the presence of C 1 -C 4 alcohol and a catalyst with a magnesium center and two ligands where one of the ligands is a propagating group and the other of the ligands is not a propagating group.

专利号:US-8895760-B2
优先权日:2010-02-26
标 题 :Process for the preparation of L-lactide of high chemical yield and optical purity
发明人：IDAGE BHASKAR BHAIRAVNATH; IDAGE SUSHEELA BHASKAR; SWAMINATHAN SIVARAM
权利人:IDAGE BHASKAR BHAIRAVNATH; IDAGE SUSHEELA BHASKAR; SWAMINATHAN SIVARAM; COUNCIL SCIENT IND RES
摘要:A process for the synthesis of 100% optically pure L(+)-lactide catalyzed by zinc and tin metal catalysts of less than 150 micron particle size is disclosed. The L-lactide obtained was further purified to obtain lactide of 100% optical purity and acid impurities less than 10 meq/kg.

专利号:US-9637507-B2
优先权日:2012-11-14
标 题:Process for the preparation of liquid tin(II) alkoxides
发明人：MEEPOWPAN PUTTINAN; PUNYODOM WINITA; MOLLOY ROBERT
权利人:CHIANG MAI UNIV
摘要:A synthetic process of producing liquid tin(II) alkoxides for use as either catalysts in the synthesis of lactide or as initiators in the polymerization of cyclic ester monomers to yield biodegradable polyesters is described. The synthetic process employs anhydrous tin(II) chloride dissolved in n-heptane mixed with dry diethylamine. Alcohols, ROH, in which the R groups are n-C 4 H 9 , n-C 6 H 13 , and n-C 8 H 17 are added to the reaction mixture and stirred for 12 hours. The reaction mixture is then filtered under nitrogen or argon before being evaporated to dryness to yield the three tin(II) alkoxides, namely: tin(II) n-butoxide, tin(II) n-hexoxide, and tin(II) n-octoxide. All three tin(II) alkoxides are viscous, dark yellow liquids which are highly soluble in most common organic solvents. Furthermore, they can all be stored under an inert atmosphere for long periods without any significant change in their reactivity and, therefore, in their effectiveness as catalysts/initiators.

专利号:WO-2023187655-A1
优先权日:2022-03-28
标题:Synthesis methods for ultra-high molecular weight polylactides and ultra-high molecular weight polylactides made therefrom
发明人：RASTOGI SANJAY; ROMANO DARIO; LI FEIJIE
权利人:UNIV KING ABDULLAH SCI & TECH
摘要:A facile method for the preparation of ultra-high molecular weight of poly(lactone) (PL) with relatively narrow polydispersity index using a Bismuth based catalyst is provided. The methods avoid the cumbersome step of monomer purification and proceed without any addition of co-initiators. Ultra-high molecular weight PL made according to the disclosed methods are also provided.

专利号:US-8940855-B2
优先权日:2009-06-02
标题:Polymers bearing pendant pentafluorophenyl ester groups, and methods of synthesis and functionalization thereof
发明人：HEDRICK JAMES L; NELSON ALSHAKIM; SANDERS DANIEL P
权利人:IBM
摘要:A one pot method of preparing cyclic carbonyl compounds comprising an active pendant pentafluorophenyl ester group is disclosed. The cyclic carbonyl compounds can be polymerized by ring opening methods to form ROP polymers comprising repeat units comprising a side chain pentafluorophenyl ester group. Using a suitable nucleophile, the pendant pentafluorophenyl ester group can be selectively transformed into a variety of other functional groups before or after the ring opening polymerization.

专利号:US-2016039782-A1
优先权日:2013-04-24
标题 :Technological method for synthesis of optically pure l-/d-lactide catalyzed by biogenic guanidine