Synthesis 2025; 57(01): 167-175
DOI: 10.1055/s-0043-1775381
paper
Special Topic Dedicated to Prof. H. Ila

Zinc Carbenoid-Promoted Methylene Insertion in Saturated Heterocycles: Mechanistic Insights and Reactivity Profiles

Masato Tsuda
a   School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta-cho Midori-ku, Yokohama 226–8501, Japan
,
a   School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta-cho Midori-ku, Yokohama 226–8501, Japan
b   Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho Midori-ku, Yokohama 226–8501, Japan
› Author Affiliations
This work was supported by JSPS Fellowship (23KJ0899) from the Japan­ Society for the Promotion of Science.


Dedicated to Professor Hiriyakkanavar Ila on her 80th birthday

Abstract

The ring expansion of saturated heterocycles through methylene insertion into N–O bonds using a zinc carbenoid is described. This transformation is applied to 1,2-oxazetidines and 1,2-oxazolidines, while N-tosylated 1,2-oxazinane affords a ring-opened product. Density functional theory calculations suggest a stepwise reaction mechanism of the ring expansion and elucidate the origins of the different reactivities observed.

Supporting Information



Publication History

Received: 19 May 2024

Accepted after revision: 19 June 2024

Article published online:
16 July 2024

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