《Accessing Dihydro-1,2-oxazine via Cloke-Wilson type Annulation of Cyclopropyl Carbonyls: Application towards the Diastereoselective Synthesis of Pyrrolo[1,2-b][1,2]oxazine》 was published in Journal of Organic Chemistry in 2020. These research results belong to Kumar, Pankaj; Kumar, Rakesh; Banerjee, Prabal. Safety of Trimethylsulfoxonium iodide The article mentions the following:
A convenient additive-free synthesis of dihydro-4H-1,2-oxazines via a Cloke-Wilson type ring expansion of the aryl substituted cyclopropane carbaldehydes (ACC) with the hydroxylamine salt was introduced. Comparatively less active cyclopropyl ketones also followed a similar protocol if supplemented by catalytic pTSA.H2O. The transformation was performed in an open-to-air flask as it showed negligible sensitivity towards air/moisture. Dihydro-4H-1,2-oxazines when subjected to cycloaddition with the cyclopropane diester, afforded a trouble-free formulation of the valued hexahydro-2H-pyrrolo[1,2-b][1,2]oxazine derivatives Cascade one-pot variant of this two-step strategy offered a comparable overall yield of the final product. In the experiment, the researchers used Trimethylsulfoxonium iodide(cas: 1774-47-6Safety of Trimethylsulfoxonium iodide)
Trimethylsulfoxonium iodide(cas: 1774-47-6) is a sulfoxonium salt. It is used to generate dimethyloxosulfonium methylide by reaction with sodium hydride. The latter compound is used as a methylene-transfer reagent, and is used to prepare epoxides.Safety of Trimethylsulfoxonium iodide
Referemce:
Iodide – Wikipedia,
Iodide – an overview | ScienceDirect Topics – ScienceDirect.com