134981-68-3Relevant academic research and scientific papers
An expeditious one-pot synthesis of diethyl N-Boc-1-aminoalkylphosphonates
Klepacz, Anna,Zwierzak, Andrzej
, p. 1079 - 1080 (2007/10/03)
A general one-pot, purification-free synthesis of diethyl N-Boc-1-aminoalkylphosphonates has been developed. The procedure involves base-catalyzed Michael-type addition of sodium diethyl phosphite to N-Boc imines generated in situ by the action of sodium
Transformation of Arylmethylamines into α-Aminophosphonic Acids via Metalated Phosphoramidates: Rearrangement of Partly Configurationally Stable N-Phosphorylated α-Aminocarbanions
Hammerschmidt, Friedrich,Hanbauer, Martin
, p. 6121 - 6131 (2007/10/03)
N-Benzyl phosphoramidate was protected at nitrogen with a TMS, p-toluenesulfonyl, Boc, lithium carboxylate, or diethoxyphosphinyl group and metalated with s-BuLi or LDA at -78 °C at the benzylic carbon. For the latter three protecting groups, the intermediate α-amino(phenylmethyl)-lithiums isomerized to N-protected α-aminophosphonates (phosphoramidate-aminophosphonate rearrangement). (R)-N-[1-2H1]Phenylmethyl phosphoramidate in combination with Boc or (EtO)2P-(O) was used to demonstrate that metalation occurs with a high primary kinetic isotope effect (kH/kD 13-50) and migration of the diethoxyphosphinyl group with retention of configuration at carbon. Furthermore, the short-lived carbanion lithium pairs are partly configurationally stable as the aminophosphonates formed with the two protecting groups have enantiomeric excesses of 79 and 24%, respectively. When homochiral lithium amides derived from (R)-N-isopropyl-1-phenylethylamine and (R,R)-N,N-di(1-phenylethyl)amine were used to induce a phosphoramidate-aminophosphonate rearrangement, chiral nonracemic α-aminophosphonates were formed (ee 26-35%). Three racemic aminophosphonates were deprotected with hot 6 M HCl and purified by ion-exchange chromatography on Dowex 50W,H+ to exemplify the transformation of phenyl-, p-tolyl-, and (1′-naphthyl)methylamine into aminophosphonic acids via lithiated phosphoramidates.
Electrophilic amination: First direct transfer of NHBoc with Li t-butyl-N-tosyloxycarbamate
Genet,Mallart,Greck,Piveteau
, p. 2359 - 2362 (2007/10/02)
Lithium t-butyl-N-tosyloxycarbamate (LiBTOC) has been found to be an electrophilic aminating reagent. This species reacts with organometallic reagents, ester enolates and α-cuprophosphonates to provide primary amines as well as α-aminocarboxylic and phosphonic esters in their N-(Boc) protected form. (35-80% isolated yields).
