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Synthesis of cyclic chiral ?-amino boronates by copper-catalyzed asymmetric dearomative borylation of indoles.

ABSTRACT: A copper(i)-catalyzed dearomative borylation of N-alkoxycarbonyl protected indole-3-carboxylates has been developed. The boron addition in this reaction occurred regioselectively at the 2-position of indoles followed by diastereoselective protonation, affording the corresponding stable cyclic chiral ?-amino boronates (2-borylindolines) in moderate to good yields with excellent diastereo- and enantioselectivities. The product 2c could be used as a versatile precursor to undergo subsequent stereoselective transformations, delivering highly functionalized 2,3,3-trisubstituted chiral indolines.

SUBMITTER: Chen L

PROVIDER: S-EPMC6050576 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Synthesis of cyclic chiral α-amino boronates by copper-catalyzed asymmetric dearomative borylation of indoles.

Chen Lili L Shen Jun-Jian JJ Gao Qian Q Xu Senmiao S

Chemical science 20180612 26

A copper(i)-catalyzed dearomative borylation of <i>N</i>-alkoxycarbonyl protected indole-3-carboxylates has been developed. The boron addition in this reaction occurred regioselectively at the 2-position of indoles followed by diastereoselective protonation, affording the corresponding stable cyclic chiral α-amino boronates (2-borylindolines) in moderate to good yields with excellent diastereo- and enantioselectivities. The product <b>2c</b> could be used as a versatile precursor to undergo subs ...[more]

PMID: 30079199

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