将平台分子及其衍生物转变为具有多种应用的高附加值的醇具有重要意义。这项研究涉及从糠醛中获得的2-甲基四氢呋喃(MTHF)的系统转化为1-戊醇乙酸酯(PA)和1,4-戊二醇乙酸酯(PDA)。详细研究了路易斯酸的种类,反应温度和氢气压力等反应参数。还进行了1 H NMR光谱和反应动力学研究,以帮助阐明反应机理。结果表明伯醇乙酸酯的裂解比仲醇乙酸酯的裂解更不容易,主要产物是PA。PA收率为91.8%(150°C,3 MPa H 2通过使用Pd / C和Sc(OTf)3作为助催化体系,可达到30分钟),使用Sc(OTf)3催化剂可达到PDA的82%收率(150°C,30分钟)。同时,通过简单的皂化将乙酸酯有效地转化为醇,并导致良好的产率。
Alcohols were acetylated or formylated with triphenylphosphine and carbon tetrabromide in ethylacetate or ethyl (or methyl) formate at room temperature. THP or TBDMS ether of primary alcohol got converted into formate or acetate under the experimental conditions employed in one pot operation.
Abstract Primary alcohols and phenols have been acetylated with acetylimidazole by the solid state reaction, grinding both substrates with a pestle in a mortar.
摘要 伯醇和酚通过固态反应与乙酰咪唑乙酰化,在研钵中用研杵研磨两种基材。
Ring opening of cyclic ethers by sulfuric acid - acetic anhydride
Cyclic ethers such as tetrahydrofuran or tetrahydropyran were easily cleaved at room temperature by sulfuricacid - aceticanhydride providing the corresponding diacetoxyalkanes in good yield. The ring opening was applicable to saturated cyclic ethers, regardless of the presence of substituent groups.
Acylative Dimerization of Tetrahydrofuran Catalyzed by Rare‐Earth Triflates
作者:William H. Miles、Daniel A. Ruddy、Samira Tinorgah、Rebecca L. Geisler
DOI:10.1081/scc-120034170
日期:2004.12.31
Abstract Ytterbium, scandium, and lanthanum triflates catalyze the cleavage reactions of cyclicethers to give various products. Most notable was the acylativecleavage of tetrahydrofuran with acetic anhydride catalyzed by Yb(triflate)3 to give the dimeric compound CH3CO2(CH2)4O(CH2)4OCOCH3 in 69% yield.
reaction that typically occurs in the vinylation of diols. In addition, the thermodynamically preferred transesterification reaction leading to the acetate esters and bis-esters was completely suppressed. DFT calculations revealed an iridium-acetate complex as the active catalytic species and they disclosed the importance of the carbonyl group of vinylacetate for the formation of a six-membered cyclic