Ring Opening Of N-tosylaziridines Research Articles

Direct Synthesis of Nitrones via Transition-Metal-Free Ring-Opening of N-Tosylaziridines with the Nitrogen Atom of Various (E)-Aldoximes and (E)-Ketoximes

The KOH-, K2CO3-, or Et3N-catalyzed ring-opening reaction of N-tosylaziridines using the nitrogen atom of a series of (E)-aldoximes and (E)-ketoximes as a nucleophilic atom instead of an oxygen atom was developed to construct various nitrones under mild reaction conditions. Diverse (E)-aldoximes and (E)-ketoximes were demonstrated to be compatible with this reaction and the products of O-ring-opening reactions were not detected for most examples.

Mechanism studies of the chemoselective ring opening of N-tosyl aziridines with aldehydes catalyzed by an N-heterocyclic carbene under aerobic conditions

The mechanism of the reaction of N-tosyl aziridines with aldehyde catalyzed by nucleophilic carbene under aerobic conditions was investigated using B97D method. Two pathways were studied based on experimental reports, and the results show the first pathway is the best one. In the first pathway, the aziridine ring-opening step is the rate-determining step with the free energy of 18.3 kcal mol−1. The addition step of one oxygen molecule to olefin forms the singlet state compound. The oxygen molecule in this system can be utilized as a source of an oxygen atom for the carboxylate product.

A Mild and Regioselective Ring-Opening of Aziridines with Acid Anhydride Using TBD or PS-TBD as a Catalyst.

The ring-opening of N-tosylaziridines with various acid anhydrides catalyzed by 5 mol % of 1,5,7-triazabicyclo[4,4,0]dec-5-ene (TBD) afforded the corresponding β-amino esters in excellent yields under mild reaction conditions. Polymer-supported catalyst, PS-TBD also acts as a good catalyst for this reaction. PS-TBD was easily recovered and reused with minimal loss of activity.

NaHSO3-Promoted Ring Openings of N-Tosylaziridines and Epoxides with H2O

Except for the N-tosyl-2-tridecylazirideine (V) all of the performed ring opening reactions of N-tosylaziridines are highly regioselective.

An Efficient Method for Opening N-Tosylaziridines with Silylated Nucleo­philes by Using Polystyrene-Supported 1,5,7-Triazabicyclo[4.4.0]dec-5-ene as a Reusable Organocatalyst

Polystyrene-supported 1,5,7-triazabicyclo[4.4.0]dec-5-ene (PS-TBD) catalyzes the ring opening of N-tosylaziridines with trimethylsilyl cyanide, trimethylsilyl azide, or trimethylsilyl halides to give the corresponding products in high yields. PS-TBD can be easily recovered and reused without significant loss of catalytic activity.

ChemInform Abstract: TBD‐Catalyzed Ring Opening of Aziridines with Silylated Nucleophiles.

Abstract The ring opening of N-tosylaziridines with silylated nucleophiles catalyzed by 1,5,7-triazabicyclo[4,4,0]dec-5-ene (TBD) afforded the corresponding β-functionalized sulfonamides in excellent yields under mild reaction conditions.

TBD-Catalyzed Ring Opening of Aziridines with Silylated Nucleophiles

The ring opening of N-tosylaziridines with silylated nucleophiles catalyzed by 1,5,7-triazabicyclo[4,4,0]dec-5-ene (TBD) afforded the corresponding β-functionalized sulfonamides in excellent yields under mild reaction conditions.

ChemInform Abstract: ZrCl4‐Catalyzed Synthesis of β‐Aminosulfides from Aziridines and Thiols.

AbstractThe zirconium tetrachloride‐promoted ring‐opening of N‐tosylaziridines with thiols is studied.

Polystyrene-supported TBD catalyzed ring-opening of N-tosylaziridines with silylated nucleophiles

Polystyrene-supported TBD (PS-TBD) catalyzes the ring-opening of N-tosylaziridines with silylated nucleophiles to give the corresponding products in high yields. PS-TBD was easily recovered and reused without significant loss of catalytic activity.

Ring Opening/C–N Cyclization of Activated Aziridines with Carbon Nucleophiles: Highly Diastereo- and Enantioselective Synthesis of Tetrahydroquinolines

A simple strategy for the synthesis of substituted tetrahydroquinolines through regio- and stereoselective ring opening of N-tosyl aziridines with carbon nucleophiles generated from 2-(bromoaryl)acetonitriles followed by palladium-catalyzed intramolecular C-N cyclization is reported in excellent yields (up to >99%) and stereoselectivity (ee and de up to >99%).

TTMPP: An efficient organocatalyst in the ring-opening of aziridines with silylated nucleophiles

The ring-opening of N-tosylaziridines with silylated nucleophiles catalyzed by tris(2,4,6-trimethoxyphenyl)phosphine (TTMPP) afforded the corresponding beta-functionalized sulfonamides in excellent yield under mild reaction conditions.

Aminolysis of N-tosylaziridines: an approach to asymmetric synthesis of symmetric and unsymmetric chiral sulfonamide ligands

The ring-opening of N-tosylaziridines with aliphatic amines can be efficiently catalyzed by lithium perchlorate to provide derivatives of the trans-1,2-diamine in high yields. The reaction was used in desymmetrization of several cyclic N-tosylaziridines using chiral amines. Using this strategy, an efficient synthesis was developed of chiral vicinal C 2 symmetric bis-(sulfonamides), unsymmetrical bis(sulfonamides) and other symmetric and unsymmetric ligands based on trans-1,2-cyclohexanediamine.

Unexpected Ring-Opening Reactions of Aziridines with Aldehydes Catalyzed by Nucleophilic Carbenes under Aerobic Conditions

[reaction: see text] The chemoselective ring opening of N-tosyl aziridines with aldehydes catalyzed by an N-heterocyclic carbene was investigated under aerobic conditions. Unexpected carboxylates of 1,2-amino alcohols from the corresponding aldehydes, rather than the acyl anion ring-opened beta-amino ketones, were exclusively obtained. A plausible mechanism for this unprecedented carbene-mediated reaction was also proposed.

Lewis Base Catalyzed Ring Opening of Aziridines with Silylated Nucleophiles.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Synthesis of chiral vicinal C2 symmetric and unsymmetric bis(sulfonamide) ligands based on trans-1,2-cyclohexanediamine by aminolysis of N-tosylaziridines

The ring opening of N-tosylaziridines with aliphatic amines can be efficiently catalyzed by lithium perchlorate to provide derivatives of the trans-1,2-diamine in high yields. The reaction was used in desymmetrization of several cyclic N-tosylaziridines using chiral amines. Using this strategy, an efficient synthesis of chiral vicinal C 2 symmetric bis(sulfonamide) and unsymmetrical bis(sulfonamide) ligands based on trans-1,2-cyclohexanediamine was developed.

Lewis Base Catalyzed Ring Opening of Aziridines with Silylated Nucleophiles

The ring opening of N-tosylaziridines with trimethylsilylated nucleophiles, catalyzed by N,N,N',N'-tetramethylethylenediamine, led to the production of beta-functionalized sulfonamides in good to excellent yields with high regioselectivity. [reaction: see text]

The synthesis of β- N-tosylamino hydroxylamines via the ring opening of N-tosylaziridines and their use in reverse Cope cyclisations

N-Tosylated aziridines have been found to undergo high yielding and regioselective ring opening with hydroxylamines in diethyl ether in the presence of boron trifluoride diethyl ether complex to give β- N-tosylamino hydroxylamines. Suitable substrates were shown to undergo reverse-Cope cyclisations to give amino functionalised pyrrolidine and piperidine N-oxides.

Ring-opening of N-tosylaziridines by heterosubstituted allyl anions. Application to the synthesis of azetidines and pyrrolidines

Ring opening of N-tosylaziridines by silyl- or phenylthio-substituted allyl anions gives N-(alk-4-enyl)tosylamides which may be cyclized to azetidines or pyrrolidines.

Reaction of Aziridines with Dianions Derived from β-Ketoesters: Application to the Preparation of Substituted Pyrrolidines

The nucleophilic ring opening of N-tosyl aziridines using the dianions derived from ß-ketoesters has been studied. Acid-mediated cyclisation of the resulting amino ß-ketoesters to a number of substituted pyrrolidines has also been examined.