1-bromo-1-ethoxycyclopropane: a new reagent for cyclobutanone synthesis
作者:Robert C. Gadwood
DOI:10.1016/s0040-4039(01)81702-0
日期:1984.1
A variety of of cyclobutanones have been prepared in high yield from 1-bromo-1-ethoxycyclopropane via lithiation, addition to aldehydes or ketones, and mild acid-catalyzedrearrangement of the adducts.
Ring-Expansion of MCPs in the Presence of DIAD or DEAD and Lewis Acids
作者:Li-Xiong Shao、Min Shi
DOI:10.1002/ejoc.200300515
日期:2004.1
Treatment of methylenecyclopropanes (MCPs) with DIAD or DEAD in MeCN under mild conditions in the presence of Lewisacid Zr(OTf)(4) gave the cyclobutanone ring-expansion products in good to high yields based on the employed DIAD or DEAD. From a deuterium labeling experiment, the oxygen atom is derived from ambient water. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004).
2,2-Dimethyl cyclopentanones by acid catalyzed ring expansion of isopropenylcyclobutanols. A short synthesis of (±)-α-cuparenone and (±)-herbertene
作者:Angela M. Bernard、Angelo Frongia、Francesco Secci、Pier P. Piras
DOI:10.1039/b505707h
日期:——
catalyzed ring expansion of isopropenylcyclobutanols; the method allows ready access to the family of sesquiterpenes cuparanes and herbertanes, as demonstrated by the synthesis of (+/-)-alpha-cuparenone and the direct precursor of (+/-)-herbertene.
Mn‐Catalyzed Ring‐Opening Peroxidation of Cyclobutanols: A Method for the Synthesis of 4‐Oxo Peroxides
作者:Chenhao Lou、Leiyang Lv、Zhiping Li
DOI:10.1002/adsc.202200705
日期:2022.11.8
A manganese-catalyzed regioselective ring-opening peroxidation of cyclobutanols has been disclosed. With this protocol, the C(sp3)−OOBu-t bond could be efficiently constructed via the radical-mediated C−C bond cleavage/coupling, allowing the facile access to a variety of 4-oxo peroxides. Besides, the obtained peroxidation products could be readily transformed into other synthetically attractive skeletons
作者:Melanie A. S. Blackburn、Corin C. Wagen、M. Raul Bodrogean、Pamela M. Tadross、Andrew J. Bendelsmith、Dennis A. Kutateladze、Eric N. Jacobsen
DOI:10.1021/jacs.3c02960
日期:2023.7.19
A catalytic protio-semipinacol ring-expansion reaction has been developed for the highly enantioselective conversion of tertiary vinylic cyclopropyl alcohols into cyclobutanone products bearing α-quaternary stereogenic centers. The method relies on the cocatalytic effect of a chiral dual-hydrogen-bond donor (HBD) with hydrogen chloride. Experimental evidence is provided for a stepwise mechanism where