Four-Component Assembly of Chiral N–B Heterocycles with a Natural Product-Like Framework

The dative N-B bond was used to simply assemble heterocycles with a skeleton akin to the 5-oxofuro2,3-bfuran motif. Twenty-five new N-B heterocycles were prepared via a highly efficient one-pot four-component reaction in yields and diastereoselectivities up to 95% and >97%, respectively. Several reaction intermediates were discovered using electrospray ionization mass spectroscopy which set the basis for the mechanism elucidation using DFT calculations.