Efficient and selective cleavage of the t-butoxycarbonyl group from di-t-butylimidodicarbonate using catalytic bismuth(III) bromide in acetonitrile

Catalytic Methyl Transfer from Dimethylcarbonate to Carboxylic Acids

“…Methyl ester 3r was isolated as a clear, colorless oil (110 mg, 83% yield, >25: 1 dr). The spectral data indicated the presence of a single diastereomer and were consistent with reported values . NMR data was acquired at elevated temperature so that peaks arising from hindered rotation around the amide bond coalesced.…”

“…Optical rotation (see Table S with reported values. 50 NMR data was acquired at elevated temperature so that peaks arising from hindered rotation around the amide bond coalesced. 1 N-(tert-Butyloxycarbonyl)-L-phenylalanine Methyl Ester (3s, CAS Registry: 51987-73-6).…”

Interfacing single-atom catalysis with continuous-flow organic electrosynthesis

“…The Boc group is one of the most widely used amino protecting groups, and the most common procedures for its removal require an excess of an organic acid such as TFA, 107 or mineral acids such as sulfuric, 108 hydrochloric, 109 and phosphoric acid 110 on large scale. However, catalytic methods are also known, and they include the use of bismuth( iii ) bromide, 111 copper( ii ) triflate, 112 iron( iii ) salts, 113 and zinc-hydroxyapatite. 114 The list is non-exhaustive but sheds some light on the versatility of the applicability of metal systems for catalytic Boc-deprotection.…”

Applications of bismuth(iii) compounds in organic synthesis

“…Jiang and co-workers have developed a BiBr 3 -catalyzed method for the cleavage of tert-butoxycarbonyl group from di-tert-butylimidodicarbonates (Scheme 11). 32 BiBr 3 in CH 3 CN was found to be an efficient catalyst for the selective deprotection of a N-Boc group in N-Boc-N-acylprotected amines. Under the reaction conditions, other protecting groups such as the Cbz group, TBDMS group and a MOM group remained unaffected.…”