Yan, Dingyuan published the artcileSynthesis of Benzofurans and Benzoxazoles through a [3,3]-Sigmatropic Rearrangement: O-NHAc as a Multitasking Functional Group, Quality Control of 209919-30-2, the publication is Organic Process Research & Development (2019), 23(8), 1646-1653, database is CAplus.
The synthesis of heterocycles relies heavily on diverse sigmatropic rearrangements triggered by the cleavage of X-Y (X, Y = C, O, N, S, I) bonds. However, a unified rearrangement approach for constructing heterocyclic libraries is highly desirable. Encouraged by computational anal. of [3,3]-sigmatropic rearrangements, we can now rapidly synthesize oxa-heterocycles by treating N-phenoxyacetamides (Ph-ONHAc) with compounds containing an sp-hybridized carbon. The generality of the process is illustrated by the late-stage diversification of natural products, including estrone and an approved drug. A combination of exptl. and computational studies revealed that the reactions proceed through a facile Claisen-like [3,3]-sigmatropic rearrangement/annulation process.
Organic Process Research & Development published new progress about 209919-30-2. 209919-30-2 belongs to chlorides-buliding-blocks, auxiliary class Chloride,Boronic acid and ester,Benzene,Boronic Acids,Boronic acid and ester, name is 4-Chloro-2-methylphenylboronic acid, and the molecular formula is C12H14O2, Quality Control of 209919-30-2.
Referemce:
https://en.wikipedia.org/wiki/Chloride,
Chlorides – an overview | ScienceDirect Topics