Axial structure of oxathiane benzyl sulfonium perchlorate

Solladié‐Cavallo, Arlette; Adib, Ahmed Rhassane El; Schmitt, Michel; Fischer, Jean; DeCian, André

doi:10.1016/s0957-4166(00)86065-6

Cited by 28 publications

(15 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…[9] N-SES, NBoc, and N-Ts imines were prepared according to literature procedures [10] and are all known compounds, except for N- ethanesulfonamide (21). N-o-Nitrobenzenesulfonamide (NoNs) imines were prepared according to a slightly modified literature procedure [11] to that used for the preparation of NpNs imines, and are new compounds except for phenyl- (7) and 4-methoxyphenyl-substituted (11) imines.…”

Section: Resultsmentioning

confidence: 99%

Sulfur Ylide Promoted Synthesis of N‐Protected Aziridines: A Combined Experimental and Computational Approach

Dokli¹,

Matanović²,

Hameršak³

2010

Chemistry A European J

View full text Add to dashboard Cite

A range of N-protected aziridines [N-Tosyl (N-Ts), N-2-trimethylsilylethanesulfonamide (N-SES), N-tert-butoxycarbonylamido (N-Boc), and N-o-nitrobenzenesulfonamide (oNs)] were prepared in moderate to good yield and with high enantiomeric excess of both isomers starting from N-protected imines, using a sulfonium salt derived from Eliel's oxathiane. The diastereoselectivities of the reactions are influenced by the imine N-protecting group, the imine substituent, and the sulfide structure. An unusual cis selectivity was observed in the formation of N-tosyl-2-phenyl-3-tert-butylaziridine and N-o-trimethylsilylethanesulfonamide-2-phenyl-3-tert-butylaziridine, which was explained by using computational models. The analysis suggests that betaine formation in the case of N-tosyl-tert-butylaldimine aziridination using oxathiane benzyl sulfonium ylide 1' is reversible and that the selectivity is determined at the rotation step, which is unusual for semistabilized ylide aziridination. We have shown herein that the steric bulk of an imine substituent, in combination with a sterically demanding sulfonium ylide, can also affect the reversibility of the reaction. This is the first example of this sort involving aziridinations using semistabilized ylides.

show abstract

Section: Resultsmentioning

confidence: 99%

Sulfur Ylide Promoted Synthesis of N‐Protected Aziridines: A Combined Experimental and Computational Approach

Dokli¹,

Matanović²,

Hameršak³

2010

Chemistry A European J

View full text Add to dashboard Cite

show abstract

“…[6,9,11] It thus appeared that EtP2 leads to the same configuration as NaH and one can postulate that the model [9,12] shown in Figure 1 holds. Therefore the same structure was assigned to the (؉, EtOH)-isomers obtained for the new and unknown trans-epoxides 1,2,3 and 4: (1R,2R)-1, (1R,2R)-2, (1S,2R)-3 and (1R,2R)-4.…”

Section: Enantiomeric Purities and Absolute Configurations Of Epoxidementioning

confidence: 97%

“…[8] Asymmetric synthesis of the epoxides 1-4 has been successfully performed following our method from the pure (R,R,R,S S )-(-)-sulfonium salt 7, [9] the corresponding commercially available aldehydes (Scheme 1) and a phosphazene base [EtP2 ϭ Et-Nϭ P(NMe 2 ) 2 (NϭP(NMe 2 ) 3 ] to generate the ylide.…”

Section: Asymmetric Synthesis Of Epoxides 1-4 With Etp2 As Basementioning

confidence: 99%

Pyridyl and Furyl Epoxides of More Than 99% Enantiomeric Purities: The Use of a Phosphazene Base

et al. 2000

View full text Add to dashboard Cite

trans‐1‐(2‐Pyridyl)‐, trans‐1‐(3‐pyridyl)‐, trans‐1(2‐furyl)‐, and trans‐1(3‐furyl)‐2‐phenyl epoxides with enantiomeric purities ranging from 96.8 to 99.8% [in favor of the (+, EtOH)‐isomer] are obtained in two steps from pure (R,R,R)‐oxathiane which is recovered (85‐90%) and reused. The chiral bidentate ligand 2‐phenyl‐(S)‐1‐(2‐pyridyl)ethanol with 99.6% ee was obtained in three steps and 67% overall isolated yield.

show abstract

“…[11] Deren 1 H-und 13 C-NMR-Spektren zeigten jeweils nur die Signale eines Diastereomers. Durch Vergleich der Spektren mit denen der bekannten Verbindung 2 a [12] wurde die axiale Anordnung der Arylmethylgruppen auch für 2 b ± d nachgewiesen. Die entsprechenden Ylide wurden dann entweder mit NaH oder EtNP(NMe 2 ) 2 ÀNP(NMe 2 ) 3 (¹Et-P 2 ª) [13] als Base synthetisiert (Tabelle 1 und 2).…”

unclassified

“…Die in allen Fällen beobachtete (R,R)-Konfiguration kann mit Hilfe des Modells erklärt werden, das bereits bei den Synthesen von Mono-und Diarylepoxiden vorgeschlagen wurde. [1,12] Darin wird angenommen, daû die Annäherung des Michael-Acceptors von der der gem-Dimethylgruppe gegenüberliegenden Seite erfolgt (Abb. 1).…”

unclassified

Zweistufige Synthese vontrans-2-Arylcyclopropancarbonsäureestern in 98–100 %ee mit Hilfe einer Phosphazenbase

Solladié‐Cavallo¹,

Diep-Vohuule

Isarno³

1998

Angewandte Chemie

View full text Add to dashboard Cite

show abstract

Axial structure of oxathiane benzyl sulfonium perchlorate

Cited by 28 publications

References 10 publications

Sulfur Ylide Promoted Synthesis of N‐Protected Aziridines: A Combined Experimental and Computational Approach

Sulfur Ylide Promoted Synthesis of N‐Protected Aziridines: A Combined Experimental and Computational Approach

Pyridyl and Furyl Epoxides of More Than 99% Enantiomeric Purities: The Use of a Phosphazene Base

Zweistufige Synthese vontrans-2-Arylcyclopropancarbonsäureestern in 98–100 %ee mit Hilfe einer Phosphazenbase

Contact Info

Product

Resources

About