The Use of N‐Boc‐1,3‐Oxazolidines as Chiral Auxiliaries in Asymmetric Synthesis

Abstract

This microreview presents the use of 1,3-oxazolidines, prepared from enantiomerically pure β-amino alcohols, as chiral inductors for the stereoselective transformation of adjacent prostereogenic C=C or C=O bonds. After a brief chronological presentation of the major advances in this field, a convenient synthesis of N-Boc-2-acyl-and -2-alkenyloxazolidines is presented, together with the use of these heterocycles in asymmetric synthesis. The important role played by the Boc group on the nitrogen of the heterocycle in these trans-

Five-membered oxaza heterocyclic compounds on the basis of epoxides and aziridines

“…Such reactions are also typical of aziridines 226 [246] 227 structurally related to epoxide 220 was synthesized [247] from chiral Garner aldehyde 4 [R 2 B = (+)-lpc 2 B or 9-BBN; Scheme 132]. The synthesis of epoxide 229 [248] through intermediate formation of compound 228 was noted in [249,250]. Epoxide 229 that is analogous to 230 was obtained as chiral intermediate product in the synthesis of polycyclic systems 231 and 232 [251] (Scheme 133).…”

2,2-Dichloro-1-[(2R,5S)-5-ethyl-2-methyl-2-propyl-1,3-oxazolidin-3-yl]ethanone

“…(Agami & Couty, 2004;Abu-Qare & Duncan, 2002;Guirado et al, 2003;Davies & Caseley, 1999). The discovery of N-dichloroacetyl oxazolidine as a herbicide safener has drawn widespread attention in agricultural biochemistry (Del Buono et al, 2007;Hatzios & Burgos, 2004).…”

Enantioselective Formal [3+2] Cycloaddition of Epoxides with Imines under Brønsted Base Catalysis: Synthesis of 1,3‐Oxazolidines with Quaternary Stereogenic Center

“…[7] In addition, the diastereocontrol of the subsequent aza-Michael addition of C would be achieved by substrate control and/or catalyst control, thus providing the 1,3-oxazolidine 4.E nantioenriched 1,3-oxazolidines can be utilized as synthetically versatile intermediates,c hiral auxiliaries, [8] and ligands in transition-metal catalysis. Thed riving force for this step would be the release of ring strain.…”