An efficient method of synthesis of isoxazolidine-fused β-lactams via base-promoted cyclization–ring opening of carbamoyl-spirocyclopropane isoxazolidines

Convenient approach to polyoxygenated dibenzo[c,e]pyrrolo[1,2-a]azepines from donor–acceptor cyclopropanes

A convenient approach to polyoxygenated tetrahydrodibenzo[c,e]pyrrolo[1,2-a]azepines from the donor–acceptor cyclopropanes has been developed.

Synthesis of fused cyanopyrroles and spirocyclopropanes via addition of N-ylides to chalconimines

DABCO-ylides react as a one-carbon source with chalconimines to afford fused cyanopyrrolesvia[4 + 1] annulation and spirocyclopropanesvia[2 + 1] annulation.

Heterocycles from methylenecyclopropanes

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.

Methyl 2-[(3RS,4RS)-3-phenyl-4-(phenyl-sulfon-yl)isoxazolidin-2-yl]acetate

In the title compound, C18H19NO5S, the five-membered isoxazolidine ring is in a half-chair conformation, and the phenyl rings are oriented at a dihedral angle of 66.53 (3)°. In the crystal, C-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional supra-molecular structure. A weak C-H⋯π inter-action is also observed between adjacent mol-ecules.