3.2 Amino Acid Derived Heterocyclic Chiral Auxiliaries: The use of Oxazolidinones, Oxazolidinethiones, Thiazolidinethiones, and Imidazolidinones

Photoluminescent Polymer Nanoparticles Based on Oxazolidine Derivatives for Authentication and Security Marking of Confidential Notes

“…In this state, the high polarity of oxazolidine increases the affinity of oxazolidine toward its colored and zwitterionic form, which also occurs after UV light irradiation. In addition, the design of aromatic oxazolidine structures containing polar groups in comparison to the extended conjugation form can show a remarkable absorbance intensity due to the formation of highly polar interactions at the colloidal level. ,, …”

“…In addition, the design of aromatic oxazolidine structures containing polar groups in comparison to the extended conjugation form can show a remarkable absorbance intensity due to the formation of highly polar interactions at the colloidal level. 32,35,76 Reversibility, photoswitchability, and stability of the photoluminescent latex nanoparticles were evaluated under several alternative UV and visible-light irradiation cycles. In this investigation, the UV−vis spectra of the latex samples were used to determine their absorbance intensities after being exposed to UV for 5 min (these analyses were done for 6 days).…”

Aldol Reaction of N-tert-Butanesulfinyl Imidates under Basic Conditions for Diastereoselective Synthesis of anti-Aldols

“…Methyl (R)-N-((R)-tert-Butylsulfinyl)-2-(1-hydroxycyclohexyl)-2phenylacetimidate (6). 6: colorless oil; 60.7 mg, 86%; [α] 7.32−7.25 (m, 3H), 4.64 (s, 1H), 3.86 (s, 3H), 2.90 (s, 1H), 1.72− 1.18 (m, 10H), 1.12 (s, 9H); 13 C NMR (100 MHz, CDCl 3 ) δ 173.…”

“…It is well-known that asymmetric aldol reactions can be carried out using the well-established Evans oxazolidinones as chiral auxiliary, as well as their thio analogues derived from natural and unnatural amino acids or amino alcohols . Recently, asymmetric aldol reactions have also been achieved using N - tert -butylsulfinyl ( N - t BS) imidates as chiral amide equivalents (Scheme a) .…”

“…It is well-known that asymmetric aldol reactions can be carried out using the well-established Evans oxazolidinones as chiral auxiliary, as well as their thio analogues derived from natural and unnatural amino acids or amino alcohols. 6 Recently, asymmetric aldol reactions have also been achieved using Ntert-butylsulfinyl (N-tBS) imidates as chiral amide 7 equivalents (Scheme 1a). 8 Aldol reactions of N-sulfinyl imidates 9−13 require titanium as the Lewis acid, which leads to formation of the reactive aza-enolate in the presence of tertiary amine, while also suppressing the reversibility of aldolization.…”