Oxidative Removal of N-(4-Methoxybenzyl) Group on 2,5-Piperazinediones with Cerium(IV) Diammonium Nitrate

Abstract

It was shown that N-(4-methoxybenzyl) group on 2,5-piperazinediones can be oxidatively removed with cerium(IV) diammonium nitrate under mild conditions, and the oxidative removal was performed in some model compounds which have several functional groups.

Novel Carbon-Carbon Bond Oxidative Cleavage of Hexabenzylhexaazaisowurtzitane by n-BuONO and (NH4)2Ce(NO3)6

“…In particular, the IR spectrum shows a strong peak at 1640 cm -1 , indicating the existence of iminium cation, which was further confirmed by 1 H NMR spectrum (δ 9.04 ppm, 2H) and 13 C NMR spectrum (δ 158. Under mild conditions, (NH 4 ) 2 Ce(NO 3 ) 6 can remove the N-(4-methoxybenzyl) group on 2,5-piperazinediones [5]. However, when 1 was exposed to (NH 4 ) 2 Ce(NO 3 ) 6 , instead of debenzylation, 2 was isolated in 59% yield.…”

“…2,4,6,8,10,12-Hexabenzyl-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.0 5,9 .0 3,11 ]dodecane (hexabenzylhexaazaisowurtzitane, 1) is an interesting polyaza "cage" compound synthesized recently [1]. In an effort to study the chemical behaviour of 1, we have explored a series of debenzylation method to remove the N-benzyl groups in 1 [2].…”

“…In an effort to study the chemical behaviour of 1, we have explored a series of debenzylation method to remove the N-benzyl groups in 1 [2]. Reductive acetyldebenzylation of 1 (H 2 , 20%Pd(OH) 2 /C, Ac 2 O) gives 2,6,8,12-tetraacetyl-4,10-dibenzyl-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.0 5,9 .0 3,11 ]dodecane [2,3], which could be further transformed to hexanitrohexaazaisowurtzitane [2]. In this communication we wish to report an unexpected carbon-carbon oxidative cleavage of 1 caused by n-BuONO and (NH 4 ) 2 Ce(NO 3 ) 6 , respectively (Scheme 1).…”

Ceric ammonium nitrate oxidation of N-(p-methoxybenzyl)lactams: competing formation of N-(hydroxymethyl)δ-lactams

“…Nevertheless, the most widely used method for deprotection involves the oxidative cleavage of the N-PMB moiety using ceric ammonium nitrate (CAN). [2][3][4][5][6][7][8][9][10][11][13][14][15][16][17][19][20][21]23,32,33 Factors such as the mild reaction conditions that are generally tolerant towards many different functional groups, the experimental simplicity, and the relatively low cost of CAN make this a method of choice.…”

Novel U-Shaped Systems Containing an Imide-Functionalized Cleft for the Study of Solvent-Mediated Electron Transfer and Energy Transfer: Synthesis and Binding Studies

“…[4] Compared to intramolecular cyclizations, [5] however, the intermolecular hydroaminations of alkynes [6] is more difficult, and only a few approaches exist. [4] Besides the established stoichiometric aminomercuration/reduction method, [7] the only catalytic reactions known are those with mercury or thallium, [6a,b] and metallocenes of zirconium, [6c] lanthanide, [6d,f] and actinide.…”