1.Synthesis of N-Boc-Propargylic and Allylic Amines by Reaction of Organomagnesium Reagents with N-Boc-Aminals and Their Oxidation to N-Boc-Ketimines.
Kano T1, Kobayashi R1, Maruoka K1. Org Lett. 2016 Jan 15;18(2):276-9. doi: 10.1021/acs.orglett.5b03446. Epub 2016 Jan 4.
Previously inaccessible N-Boc-protected propargylic and allylic amines were synthesized by the reaction between N-Boc-aminals and organomagnesium reagents through the in situ generated N-Boc-imine intermediates. The obtained N-Boc-propargylic amines could be readily converted into unprecedented N-Boc-ketimines by oxidation with manganese dioxide.
2.Copper-catalyzed borylative coupling of vinylazaarenes and N-Boc imines.
Smith JJ1, Best D1, Lam HW1. Chem Commun (Camb). 2016 Feb 25;52(19):3770-2. doi: 10.1039/c6cc00603e.
Cu-catalyzed three-component couplings of vinylazaarenes, B2(pin)2, and N-Boc imines are described. Oxidation of the initially formed boronate gives azaarene-containing, Boc-protected amino alcohols with reasonable to good diastereoselectivities.
3.Direct Amidation of N-Boc- and N-Cbz-Protected Amines via Rhodium-Catalyzed Coupling of Arylboroxines and Carbamates.
Lim DS1, Lew TT1, Zhang Y1. Org Lett. 2015 Dec 18;17(24):6054-7. doi: 10.1021/acs.orglett.5b03061. Epub 2015 Nov 25.
N-Boc- and N-Cbz-protected amines are directly converted into amides by a novel rhodium-catalyzed coupling of arylboroxines and carbamates, replacing the traditional two-step deprotection-condensation sequence. Both protected anilines and aliphatic amines are efficiently transformed into a wide variety of secondary benzamides, including sterically hindered and electron-deficient amides, as well as in the presence of acid-labile and reducible functional groups.