14800-16-9

Usage

Chemical Group

Alkylbenzenes

Physical State

Colorless liquid

Odor

Mild, aromatic

Solubility

Insoluble in water, soluble in organic solvents

Uses

a. Solvent in the production of rubber, resin, coatings, adhesives, and sealants
b. Chemical intermediate in the production of pharmaceuticals and fragrance compounds

Environmental and Health Risks

Low acute toxicity, not classified as carcinogenic or mutagenic

Safety Precautions

Handle and use with caution, follow proper safety measures to prevent potential hazards

InChI:InChI=1/C18H30/c1-4-7-10-16-13-14-17(11-8-5-2)18(15-16)12-9-6-3/h13-15H,4-12H2,1-3H3

Upstream product

• 693-02-7 hex-1-yne 
• 74-86-2 acetylene 
• 75-05-8 acetonitrile 
• 172481-12-8 [Ti(N-4-C₆H₄Me)Cl₂(pyridine)3] 
• 24886-73-5 1-Azidoadamantane 
• 201230-82-2 carbon monoxide 
• 292638-85-8 acrylic acid methyl ester 

Relevant academic research and scientific papers

Direct Evidence for a [4+2] Cycloaddition Mechanism of Alkynes to Tantallacyclopentadiene on Dinuclear Tantalum Complexes as a Model of Alkyne Cyclotrimerization

A dinuclear tantalum complex, [Ta2Cl6(μ-C4Et4)] (2), bearing a tantallacyclopentadiene moiety, was synthesized by treating [(η2-EtC≡CEt)TaCl3(DME)] (1) with AlCl3. Complex 2 and its Lewis base adducts, [Ta2Cl6(μ-C4Et4)L] (L=THF (3a), pyridine (3b), THT (3c)), served as more active catalysts for cyclotrimerization of internal alkynes than 1. During the reaction of 3a with 3-hexyne, we isolated [Ta2Cl4(μ-η4:η4-C6Et6)(μ-η2:η2-EtC≡CEt)] (4), sandwiched by a two-electron reduced μ-η4:η4-hexaethylbenzene and a μ-η2:η2-3-hexyne ligand, as a product of an intermolecular cyclization between the metallacyclopentadiene moiety and 3-hexyne. The formation of arene complexes [Ta2Cl4(μ-η4:η4-C6Et4Me2)(μ-η2:η2-Me3SiC≡CSiMe3)] (7b) and [Ta2Cl4(μ-η4:η4-C6Et4RH)(μ-η2:η2-Me3SiC≡CSiMe3)] (R=nBu (8a), p-tolyl (8b)) by treating [Ta2Cl4(μ-C4Et4)(μ-η2:η2-Me3SiC≡CSiMe3)] (6) with 2-butyne, 1-hexyne, and p-tolylacetylene without any isomers, at room temperature or low temperature were key for clarifying the [4+2] cycloaddition mechanism because of the restricted rotation behavior of the two-electron reduced arene ligands without dissociation from the dinuclear tantalum center.

CYCLOTRIMERIZATION AND POLYMERIZATION OF 1-HEXYNE CATALYZED BY GROUP 5, 6 TRANSITION METAL CHLORIDES.

1-Hexyne could be cyclotrimerized selectively and quantitatively by NbCl//5 and TaCl//5. The cyclotrimer formed consisted of 1,2,4- and 1,3,5-isomers. The 1,2,4/1,3,5 isomer ratio of the product was about 70/30-80/20 with NbCl//5, and about 55/45-70/30 wi

Permethyltitanocene-bis(trimethylsilyl) acetylene, an efficient catalyst for the head-to-tail dimerization of 1-alkynes

In the series of the (C5H5 - nMen)2Ti[η2-C2(SiMe3)2] (n = 0-5) (1A-1F) complexes only (C5Me5)2Ti[η2-C2(SiMe

Synthesis and Structures of Bis(indolyl)-Coordinated Titanium Dichlorido Complexes and Their Catalytic Application in the Cyclotrimerization of Alkynes

The impact of the terminal ligands on the titanium center on the coordination features of deprotonated 2,2′-bis(indolyl)methanes (henceforth: bis(indolyl)s) was studied via a structural comparison between {bis(indolyl)}Ti(NEt2)2 complexes and the corresponding dichlorido complexes. As a result, several flexible aspects of bis(indolyl) coordination were found. For example, it was revealed that an η1-coordinated indolyl moiety can change its coordination mode to coordination via the five-membered ring of indolyl when the terminal diethylamido ligands are replaced by chlorido ligands. Moreover, we found that the methoxy group in the central aromatic ring of the bis(indolyl) ligand can coordinate to the titanium center. The synthesized dichlorido complexes were applied for catalytic alkyne cyclotrimerization reactions, as Ti-based catalyst systems are less developed than Co-, Ni-, Ru-, Rh-, and Ir-based systems. During this study, the cyclotrimerization of HCCSiMe3 was found to preferentially produce the 1,3,5-form (1,3,5-form:1,2,4-form = 79:21), contrary to the typical trend of transition-metal-mediated alkyne cyclotrimerization, and the isolated yield (72%) is the highest among the known 1,3,5-favoring reactions using Ti-based catalyst systems. Furthermore, the reaction mechanism was experimentally verified to proceed through a typical stepwise mechanism involving monomeric species.

H-BPin/KOtBu Promoted Activation of Cobalt Salt to a Heterotopic Catalyst for Highly Selective Cyclotrimerization of Alkynes

A mixture of HBPin with KOtBu was found to activate cobalt salt to form a heterotopic cobalt species that is highly active for catalytic intermolecular trimerization of alkynes. This protocol affords 1,2,4-regioisomers in good yields with high regioselectivities under mild conditions. These salient features, together with the operational simplicity and high efficiency, as well as obviating the use of any costly and/or air sensitive ligands, renders the protocol promising for practical applications.

Cyclotrimerization of alkynes catalyzed by a self-supported cyclic tri-nuclear nickel(0) complex with α-diimine ligands

A cyclic tri-nuclear α-diimine nickel(0) complex [{Ni(μ-LMe-2,4)}3] (2) was synthesized from a “pre-organized”, trimerized trigonal LNiBr2-type precursor [Ni3(μ2-Br)3(μ3-Br)2(LMe-2,4)3]·Br (1; LMe-2,4 = [(2,4-Me2C6H3)NC(Me)]2). In complex 2, the α-diimine ligands not only exhibit the normal N,N′-chelating mode, but they also act as bridges between the Ni atoms through an unusual π-coordination of a C═N bond to Ni. Complex 2 is able to catalyze the cyclotrimerization of alkynes to form substituted benzenes in good yield and regio-selectivity for the 1,3,5-isomers, which is found to vary with the nature of the alkyne employed. This complex represents a convenient self-supported nickel(0) catalyst with no need for additional ligands and reducing agent.

Catalytic activity of a large Rhodium metallaborane towards the [2+2+2] cycloaddition of alkynes

Rhodadecaborane [6-(η5-C5Me5)-nido-6-RhB9H13] (1) was found to be able to catalyze the [2+2+2] cycloaddition of a series of terminal and internal alkynes to yield mixtures of 1,2,4- and 1,3,5-substituted benzene. The reactivity of compound 1 with alkynes demonstrates that decaborane based metallaborane can be used as the catalyst for [2+2+2] cycloaddition of alkynes. All compounds are characterized by NMR spectroscopy and MS spectrometry methods.

Alkyne [2 + 2 + 2] Cyclotrimerization Catalyzed by a Low-Valent Titanium Reagent Derived from CpTiX3 (X = Cl, O- i-Pr), Me3SiCl, and Mg or Zn

Inter-, partially intra-, and intramolecular [2 + 2 + 2] cycloadditions of alkynes were catalyzed by a low-valent titanium species generated in situ from the reduction of CpTi(O-i-Pr)3, CpTiCl3, or Cp?TiCl3 with Mg or Zn powder in the presence of Me3SiCl. The role of Me3SiCl as an additive in the reaction mechanism is discussed.

Cobalt Octacarbonyl-Catalyzed Scalable Alkyne Cyclotrimerization and Crossed [2 + 2 + 2]-Cycloaddition Reaction in a Plug Flow Reactor

Cobalt-catalyzed alkyne cyclotrimerization and crossed [2 + 2 + 2] cycloadditions are developed in a plug flow reactor. The protocol generally uses 5 mol % of Co2(CO)8 and is scalable at least at multigram scale. Efficient and scalable use of Co2(CO)8 for crossed reactions of diynes and alkynes has hardly any precedent.

Oxidative nitrene transfer from azides to alkynes via Ti(ii)/Ti(iv) redox catalysis: Formal [2+2+1] synthesis of pyrroles

Catalytic oxidative nitrene transfer from azides with the early transition metals is rare, and has not been observed without the support of redox noninnocent spectator ligands. Here, we report the formal [2+2+1] coupling of azides and alkynes via TiII/TiIV redox catalysis from simple Ti halide imido precatalysts. These reactions yield polysubstituted N-alkyl pyrroles, including N-benzyl protected pyrroles and rare examples of very electron rich pentaalkyl pyrroles. Mechanistic analysis reveals that [2+2+1] reactions with bulky azides have different mechanistic features from previously-reported reactions using azobenzene as a nitrene source.