Unnatural Amino Acids. 2. Simple Method of Obtaining Esters of Aziridine-2-carboxylic Acids by a Transesterification Reaction

Synthesis of Aminomethylene-gem-bisphosphonates Containing an Aziridine Motif: Studies of the Reaction Scope and Insight into the Mechanism

“…Differences of reactivity between N -Boc and N -Cbz substrates support this assumption as the benzyl oxide ion may be considered as a better leaving group than the tert -butyl oxide one. This kind of addition/elimination occurring on a carbamate moiety has already been reported in the literature . In addition, an acyl derivative of the 2-benzylaziridine treated in our conditions (data not shown) did not lead to the formation of the corresponding AzbisP, which indicated the key role of the carbamoyl moiety.…”

“…This kind of addition/elimination occurring on a carbamate moiety has already been reported in the literature. 37 In addition, an acyl derivative of the 2benzylaziridine treated in our conditions (data not shown) did not lead to the formation of the corresponding AzbisP, which indicated the key role of the carbamoyl moiety.…”

Asymmetric Total Syntheses of (−)-Renieramycin M and G and (−)-Jorumycin Using Aziridine as a Lynchpin

“…Syntheses of aziridines 9 and 11 are shown in Scheme 2. Treatment of a 1,2-dichloroethane solution of commercially available N-trityl-L-serine methyl ester (13) with MsCl and DIPEA at -78 °C followed by heating to reflux afforded directly the aziridine 14 in 73% yield. Removal of the N-trityl group under mild acidic conditions followed by N-tertbutoxycabonylation afforded N-Boc aziridine 15 in 89% overall yield, which was in turn converted to the desired (S)di-tert-butyl aziridine-1,2-dicarboxylate (11) (85%) by a transesterification with lithium tert-butoxide.…”

An Easy Route to Aziridine Ketones and Carbinols

“…Tetrahydrofuran was distilled from Na/benzophenone. Esters 1a and 1b were prepared according to the literature from aziridine-2-carboxylate in reactions with Boc-anhydride [ 22 ] and trityl-chloride [ 23 ], respectively. Ester 1c was obtained in the reaction of benzyl aziridine-2-carboxylate with Boc-anhydride [ 23 ].…”

“…Esters 1a and 1b were prepared according to the literature from aziridine-2-carboxylate in reactions with Boc-anhydride [ 22 ] and trityl-chloride [ 23 ], respectively. Ester 1c was obtained in the reaction of benzyl aziridine-2-carboxylate with Boc-anhydride [ 23 ]. Activated bis-Boc amides 2a,b were prepared by the 4-dimethylaminopyridine (DMAP)-catalyzed reaction of the corresponding amide with Boc 2 O [ 24 ].…”