176729-84-3

Basic information

• Product Name: 1-(toluene-4-sulfonyl)-2,3,4,7-tetrahydro-1H-azepine
• Synonyms: 1-(toluene-4-sulfonyl)-2,3,4,7-tetrahydro-1H-azepine
• CAS NO: 176729-84-3
• Molecular Weight: 251.349
• Mol File: 176729-84-3.mol

Chemical Properties

• CAS DataBase Reference: 1-(toluene-4-sulfonyl)-2,3,4,7-tetrahydro-1H-azepine(CAS DataBase Reference)
• NIST Chemistry Reference: 1-(toluene-4-sulfonyl)-2,3,4,7-tetrahydro-1H-azepine(176729-84-3)
• EPA Substance Registry System: 1-(toluene-4-sulfonyl)-2,3,4,7-tetrahydro-1H-azepine(176729-84-3)

Safety Data

• Hazardous Substances Data: 176729-84-3(Hazardous Substances Data)

Upstream product

• 176729-83-2 N-allyl-4-methyl-N-(pent-4-en-1-yl)benzenesulfonamide 
• 54436-57-6 (allyl)(pent-4-enyl)amine 
• 98-59-9 p-toluenesulfonyl chloride 
• 50487-71-3 4-methyl-N-(2-propenyl)benzenesulfonamide 

Relevant articles and documents

Stability and activity of cis-dichloro ruthenium olefin metathesis precatalysts bearing chelating sulfur alkylidenes

S-Chelated Grubbs type complexes are usually found in their stable cis-dichloro conformation. These precatalysts are usually latent and necessitate external stimuli to promote olefin metathesis reactions. Herein we report the synthesis of new S-chelated ruthenium complexes, by a simple exchange of the benzylidene to an alkylidene chelating ligand. The structure of the complexes was studied by NMR spectroscopy, single crystal X-ray diffraction and DFT calculations. The new complexes were tested in a series of olefin metathesis reactions and were found to be the first cis-dichloro ruthenium precatalysts that are active at room temperature. The observed differences in reactivity and structure between the alkylidene complexes and their benzylidene counterparts highlight the important influence aromaticity may have on the stability and activity of chelated Grubbs type complexes. The findings may also have implications to develop alternative strategies to stabilize, or destabilize, other organometallic complexes bearing relevant chelating ligands.

Highly Selective Olefin Metathesis with CAAC-Containing Ruthenium Benzylidenes

Several olefin metathesis reactions are studied, namely, jojoba oil oligomerization, methyl oleate self-metathesis, ring-closing metathesis (RCM) to form a nitrogen heterocycle, and 1,5-hexadiene acyclic diene metathesis polymerization (ADMET). The catalyst containing the Bertrand-Grubbs cyclic alkyl amino carbene (CAAC) ligand showed high selectivity by diminishing isomerization reactions; this was especially clear at high temperatures where the more widely used nitrogen heterocyclic carbene (NHC)-based catalysts show side reactions. Experimental and computational studies determined that it is much more difficult to produce ruthenium hydrides with CAAC, a property that can explain the improved observed activity. This finding opens a pathway for the development of even more selective olefin metathesis catalysts for reactions that require harsh conditions.

Synthesis and Catalytic Properties of Sulfur-Chelated Ruthenium Benzylidenes Bearing a Cyclic (Alkyl)(amino)carbene Ligand

Sulfur-chelated ruthenium olefin metathesis precatalysts that possess cyclic (alkyl)(amino)carbenes (CAAC) can benefit from the synergetic effect of both ligands. Changing the steric bulk of the CAAC ligand by using different substitution patterns was shown to affect the geometry of the complexes produced and determined whether the complexes could be catalytically dormant. The cis-dichloro latent catalysts could be activated both by heat or light, even in the visible region, for representative acyclic diene metathesis and ring-opening metathesis polymerization reactions, olefin cross-metathesis, and ring-closing metathesis without isomerization byproducts. Thus, these complexes were shown to combine the uniqueness of CAAC-containing Ru olefin metathesis catalysts with the advantage of the thermal and photolatency imposed by sulfur chelation of the benzylidene.

Unexpected results of a turnover number (TON) study utilising ruthenium-based olefin metathesis catalysts

A turnover number (TON) study of ruthenium-based metathesis catalysts has been conducted for ring-closing metathesis (RCM) in dilute solution. Unexpectedly the results indicate that 1st generation metathesis catalysts can give higher TON in RCM

Modulation of olefin metathesis reactions by chelation

We describe the modulation of catalytic activities by adjacent chelating entities as a new and hitherto unknown principle. It is demonstrated for ring-closing metathesis (RCM) as well as for cross metathesis (CM) reactions. For this purpose, we have modified a Hoveyda-type metathesis catalyst by employing two different chelators. Complexation of the chelators led to an electron-withdrawing effect that resulted in enhanced catalytic activity. This enhancement was dependent on the complexed metal ion and allowed a gradual adjustment of the activity of the catalyst. The application of this new approach might be extendable to other catalytic systems as well. Copyright

Latent Ruthenium Benzylidene Phosphite Complexes for Visible-Light-Induced Olefin Metathesis

Herein we report two ruthenium benzylidene complexes with benzylphosphite ligands for olefin metathesis. Unlike the previously reported benzylidene phosphite complexes, the benzylphosphite complexes adopt a cis-dichloro configuration making them latent at ambient temperatures. Irradiation with visible light (420 nm and blue LED) prompts activation of the complexes and induces catalysis of olefin metathesis reactions. One of the complexes, cis-Ru-1, was found to be especially suitable for 3D printing of multilayered polydicyclopentadiene structures with excellent spatial resolutions. Additionally, complex cis-Ru-2 was designed with a chromatic orthogonal "kill switch" based on the 2-nitrobenzyl chemistry, allowing the destruction of the catalyst upon exposure to UV-C light.

Design of bis-NHC Ru-complexes featuring diarylmethylene N-substituents for olefin metathesis

New ruthenium indenylidene complexes containing N-heterocyclic carbene (NHC) ligands were synthesized and evaluated in olefin metathesis. The presence of two symmetrical saturated NHCs featuring N-diarylmethylene fragments (R= H, OMe or F) led to robust ruthenium precatalysts with a good latency. A kinetic study was investigated showing that a thermal stimulus (>60 °C) is required to reach an efficient catalytic initiation. Interestingly, a slight electronic effect was observed depending on the presence of an electron-donating or –withdrawing group within the diarylmethylene moiety. These complexes showed good activity at 1 mol% of catalyst loading in selected ring-closing metathesis (RCM) and cross-metathesis (CM) transformations.

Activation of olefin metathesis complexes containing unsymmetrical unsaturated N-heterocyclic carbenes by copper and gold transmetalation

The activation of ruthenium-indenylidene complexes containing two unsymmetrical unsaturated N-heterocyclic carbenes (u2-NHCs) by a transmetalation process is reported. The use of copper(i) or gold(i) chlorides promotes the rapid trapping of one NHC ligand, which releases the catalytically active Ru-species. Impressive initiation rates with full-conversions are observed within one minute. This practical protocol demonstrates excellent catalytic performances in various ring-closing metathesis (RCM) and self-metathesis (SM) reactions.

Light-and Thermal-Activated Olefin Metathesis of Hindered Substrates

Efficient light-and thermal-Activated metathesis reactions of tetra-substituted olefins were obtained by the S-chelated ruthenium precatalyst Tol-SCF3. Its reactivity in a series of benchmark olefin metathesis reactions was compared to previous

Carboxyl Graphene as a Superior Support for Bulky Ruthenium-Based Olefin Metathesis Catalyst

A Hoveyda-type catalyst decorated with two quaternary ammonium tags was synthesized and noncovalently grafted on SiO2, SBA-15, and on carboxyl graphene. A comparative study showed that the efficiency of the dual-anchored heterogeneous catalysts was highly dependent on the properties of the supporting material with graphene outperforming silicate supports. The graphene-immobilized complex exhibited excellent efficiency reflected in turnover numbers obtained in ring-closing metathesis and in self-metathesis of 1-decene. Importantly, the solid-supported catalyst assured increased recyclability with no ruthenium leaching as confirmed by inductively coupled plasma mass spectrometry.