Bi(III) halides as efficient catalysts for the O-acylative cleavage of tetrahydrofurans: an expeditious entry to tetralins
作者:Simon J. Coles、James F. Costello、William N. Draffin、Michael B. Hursthouse、Simon P. Paver
DOI:10.1016/j.tet.2005.02.080
日期:2005.5
O-acylative cleavage of tetrahydrofurans using organic acid halides with catalytic Bi(III) halides is reported. X-ray crystallography is used to rationalise the failure of the reaction in the case of certain crowded acid chlorides, and a useful aspect of chemoselectivity is revealed. The synthetic potential of this reaction is illustrated with a highly efficient O-acylative cleavage/intramolecular
Various cyclic and acyclic ethers are efficiently cleaved with acyl chlorides or bromides to give ω-chloro- or ω-bromoesters under high-pressure conditions.
Palladium(II) acetate catalyzed acylative cleavage of cyclic and acyclic ethers under neat conditions
作者:Jean Fotie、Brandy R. Adolph、Shreya V. Bhatt、Casey C. Grimm
DOI:10.1016/j.tetlet.2017.10.080
日期:2017.12
During the development of a palladiumcatalyzed C–H activation cross-coupling reaction involving acyl halides, it was noted that palladium(II) acetate catalyzes the acylative cleavage of tetrahydrofuran (used as a solvent) at room temperature to afford the corresponding 4-chlorobutyl ester derivative. After optimization, the reaction was shown to work well with epoxides, oxetane and tetrahydrofuran
A silver-catalyzed chlorination of benzylic, tertiary, and secondary C(sp3)–H bonds was developed. The reaction proceeded with as low as 0.2 mol % catalyst loading at room temperature under air atmosphere with synthetically useful functional group compatibility. The regioselectivity and reactivity tendencies suggest that the chlorination proceeded through a radical pathway, but an intermediate alkylsilver
an efficient catalyst for the acylativecleavage of C–O bond of ethers with acyl chlorides. When acyclic ethers were allowed to react with acyl chlorides in the presence of a catalytic amount of ReBr(CO)5, acylativecleavage of C–O bond of acyclic ethers smoothly proceeded to give the corresponding esters in moderate to good yields. Similarly, cyclicethers were acylative cleaved by acyl chlorides to
发现rh络合物是醚与酰氯的C-O键的酰基化裂解的有效催化剂。当在催化量的ReBr(CO)5存在下使无环醚与酰氯反应时,无环醚的C-O键的酰基裂顺利进行,从而以中等至良好的收率得到了相应的酯。类似地,使用Re 2 O 7催化剂将环醚酰基氯酰化裂解,得到高产率的相应的氯取代的酯。