Heterocycles from methylenecyclopropanes

Abstract

The discovery of a series of novel organic reactions has made methylenecyclopropanes (MCPs) some of the most popular building blocks in synthetic organic chemistry during the past two decades. Among reported works, the construction of heterocycles from MCPs has highlighted new synthetic methodologies that afford more opportunities for the quick synthesis of elaborately substituted products, and this should draw a great deal of attention. However, reviews in this area are insufficient, and the latest monograph on heterocycle synthesis from MCPs was published 12 years ago. This review aims to summarize the novel organic reactions of MCPs to produce heterocycles published in recent years, which have provided specific and powerful tools for organic synthesis.

TFA‐Prompted/Rh(III)‐Catalysed Chemoselective C3− or C2−H Functionalization of Indoles with Methylenecyclopropanes

“…The development of versatile reagents and novel reaction manifolds for assembling complex structures from simple, readily accessible raw materials is extremely important in C−H functionalization field [1] . Diversified substrates and coupling partners (CPs) have been developed up to date, among which methylenecyclopropanes with the equipment of an alkene moiety and the strained cyclopropyl ring receive a great interest for their efficient and switchable reactivity which have been well‐explored in diverse transition metal (TM)‐catalyzed C−H functionalization reactions [2] . Pioneering works from the research group of Cui [3a] and Li [3b] et al .…”

TBHP-mediated oxidative synthesis of substituted pyrimido[4,5-d]pyrimidines fromN-uracil amidines and methylarenes under metal free conditions

“…2 Over the past few decades, great efforts have been made to develop novel and efficient methods for the construction of nitrogen containing heterocycles. 3 Pyrimidines are one of the most important nitrogen heterocycles, exhibiting remarkable pharmaceutical activities. 4 Among them, pyrimido [4,5-d]pyrimidines are very important scaffolds found in many natural products and synthetic drugs or drug candidates exhibiting a wide range of biological activities.…”

Recent Advances in the Cycloisomerizations of Methylenecyclopropanes using Gold Catalysis

“…[2] Amongh ighly strained small-rings, methylenecyclopropanes (MCPs) containing the smallest carbocycle with an exo-methylene moiety,a re readily accessiblec ompoundsw hich are useful buildingb locks for the synthesis of natural products and medicine precursors because of their uniques tructure and electronic properties. [3] The attractive feature of MCPs is their surprising stabilityi nd espite of containing high ring strain. [3b] Since the middle of 1970's, the transformationso fM CPs have been extensively explored under transition metal catalysis.…”