4 Carbene Manufacturers in 2024
This section provides an overview for carbenes as well as their applications and principles. Also, please take a look at the list of 4 carbene manufacturers and their company rankings. Here are the top-ranked carbene companies as of November, 2024: 1.Strem Chemicals, Inc, 2.Tokyo Chemical Industry Co., Ltd., 3.FUJIFILM Wako Pure Chemical Corporation.
Table of Contents
What Is a Carbene?
Basic Structure of Carbenes
Carbenes is a general term for carbon species that have only six valence electrons, are electronically neutral (uncharged), and have a divalent bond at the carbon center.
The six valence electrons for a divalent bond mean that it has two active electrons in the center. Analogues of the homologous elements include silylene and germylene.
It is often contrasted with carbocation, a three-coordinated chemical species with six valence electrons and a positive charge, and carbanion, a three-coordinated chemical species with eight valence electrons and a negative charge. The simplest structure of carbenes is methylene (Methylene) CH2. This substance can be generated by the decomposition of diazomethane.
Uses of Carbenes
A decade ago, carbenes were considered unstable chemical species, but in recent years there have been an increasing number of reports of carbenes being isolated through the use of ingenious molecular structures, such as electron donation by adjacent substituents and stereo-conformational fixation by bulky substituents. However, since they are not stable enough to be sold as products, precursors are sold and are basically prepared on the fly.
Because of their high reactivity, they are used as synthetic intermediates in organic synthetic chemistry. A typical reaction is the addition to a carbon-carbon double bond to form a cyclopropane ring. Insertion reactions occur for carbon-hydrogen, nitrogen-hydrogen, or oxygen-hydrogen bonds.
Many N-heterocyclic carbenes (NHC), which are cyclic carbene species sandwiched between two adjacent nitrogen atoms, have been synthesized and reported to be stable through the use of molecular structural innovations. These carbenes are widely used as ligands for organometallic complexes because of their strong metal-coordination ability. Examples include those substituted with mesityl or 2,6-diisopropylphenyl groups.
Properties of Carbenes
1. Structural Properties of Carbenes
Carbenes are classified into singlet and triplet carbenes according to the spin state of their valence electrons.
Singlet carbenes are classified into the following two categories according to the form of hybridization on carbon. In most cases, the former sp2 hybridization form is more stable.
- sp2 hybridized: 2 electrons in each of the 3 sp2 orbitals, leaving one empty p orbital
- sp3 hybridized: 2 electrons in each of the 3 sp3 orbitals with one empty sp3 orbital remaining
There are two types of triplet carbenes: sp2 hybridized and sp3 hybridized. In the latter type, two of the four sp3 orbitals are filled with two electrons each, and the remaining two sp3 orbitals are occupied by one electron of the same spin.
Which of these structures is more stable depends on factors such as the electrical and structural nature of the substituents on the carbon. In general, singlet carbenes often exhibit electrophilic reactivity, while triplet carbenes exhibit radical reactivity due to unpaired electrons.
2. Preparation of Carbenes
One of the methods for the formation of carbenes is the desorption reaction of nitrogen molecules from diazo compounds. In most cases, the reaction is triggered by heat, light, or a catalyst.
Dichlorocarbenes are also known to be formed by the action of a strong base on chloroform. The intermediate in this reaction is the trichloromethyl anion.
Imidazolidene, formed by the reaction of an imidazolium salt with a base, is another well-known carbenes species. This molecular species, formed by the desorption of a proton from the imidazole ring, is strongly stabilized by the nitrogen atoms on both sides. For this reason, the systematic species of imidazolidinylidene is used as a ligand in many transition metal catalysts.
Types of Carbenes
Carbenes, as mentioned above, are not stable molecular species and are therefore essentially not commercially available. If one wishes to use them, one must purchase precursors and prepare them for use.
Typical examples used in synthetic chemistry include the following:
- Carbenes species obtained by desorbing N2 molecules from α-diazoketones (used in the Wolf rearrangement)
- Dichlorocarbenes (obtained from chloroform and a strong base via trichloromethyl anion)
- N-Heterocyclic Carbenes (NHC) and their metal complexes (obtained by the reaction of imidazolium salts with a base)
List of 4 Carbene Manufacturers
*Including some distributors, etc.
Sort by Features
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- Company Size: largest first
- Year Founded: oldest first
- Year Founded: earliest first
Sort by Area
- Japan
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Tokyo Chemical Industry Co., Ltd.
N-Heterocyclic Carbene (NHC) Ligands
Manufacturer Overview
TCI America (TCI) was founded in 1946 and is a worldwide manufacturer of specialty organic chemicals. The company produces organic laboratory chemicals as well as pharmaceutical, cosmetic, and functional materials. TCI’s product segments include Chemistry, Life Science, Materials Science, Analytical Chemistry, and Custom & Bulk. For materials science, the company manufactures battery materials, nanocarbon materials, and magnetic materials. For life sciences, the company produces antibodies, reagents, and chemicals for cancer research. The company produces HLC, NMR, various chemicals, and resins and media for analytical chemistry.
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FUJIFILM Wako Pure Chemical Corporation
N-Heterocyclic Carbene (NHC) Ligands
Manufacturer Overview
FujiFilm Wako Pure Chemical Corporation, founded in 1922 and headquartered in Osaka, Japan, is a manufacturer of laboratory chemicals, specialty chemicals, and clinical diagnostic reagents. The company has three business domains, namely laboratory chemicals, specialty chemicals, and clinical diagnostic reagents, and some of its products include biochemistry reagents, blood transfusion test drugs, battery materials, polymer-related materials, and general reagents. The products are useful in various fields, including electronic, cosmetic, polymeric, pharmaceutical, and medical care. It acquired Sibayagi Co. Ltd. in 2015 and provides custom manufacturing to meet customer requirements.
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Strem Chemicals, Inc
N-Heterocyclic Carbenes (NHCs)
Manufacturer Overview
Strem Chemicals, Inc, founded in 1964, is an American manufacturer and supplier of high-purity specialty chemicals and materials, based in Newburyport, Massachusetts. Acquired by Ascensus Specialties, another American chemical company in 2021, Strem offers a catalog of over 6,000 specialty products under the metal, inorganic, organometallic, and nanomaterial categories. Some of their diverse product offerings include metal catalysts for organic synthesis, metal carbonyls, metal organic chemical vapor deposition (MOCVD) and atomic layer deposition (ALD) precursors. Strem serves global customers, particularly academic, governmental, and industrial research and development laboratories. Their products find applications in various industries, including microelectronics, chemicals, petrochemicals, and pharmaceuticals.
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MilliporeSigma
Carbene
Manufacturer Overview
Millipore Sigma, formerly known as Sigma-Aldrich, was created in 175 through the merger of Sigma Chemical Company and Aldrich Chemical company and today is a subsidiary of Merck. Millipore Sigma is a life science and biotechnology company serving the industry with several products and services. Some of their product categories include peptide synthesis materials, biochemicals, building blocks, catalysts, chemical biology, chemical synthesis, flavors & fragrances, formulation, lab chemicals, lab safety, APIs, and stable isotopes. Services include characterization, contract manufacturing, custom products, software, support, testing, and mRNA development & manufacturing.
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Carbene Manufacturer Ranking
*Including some distributors, etc.Ranking as of November 2024
Derivation Method| Rank | Company | Click Share |
|---|---|---|
| 1 | Strem Chemicals, Inc |
33.3%
|
| 2 | Tokyo Chemical Industry Co., Ltd. |
33.3%
|
| 3 | FUJIFILM Wako Pure Chemical Corporation |
33.3%
|
Derivation Method
The ranking is calculated based on the click share within the carbene page as of November 2024. Click share is defined as the total number of clicks for all companies during the period divided by the number of clicks for each company.Number of Employees
Newly Established Company
- Strem Chemicals, Inc: 1964 (60 years ago)
- Tokyo Chemical Industry Co., Ltd.: 1946 (78 years ago)
- FUJIFILM Wako Pure Chemical Corporation: 1922 (102 years ago)
Company with a History
- FUJIFILM Wako Pure Chemical Corporation: 1922 (102 years ago)
- Tokyo Chemical Industry Co., Ltd.: 1946 (78 years ago)
- Strem Chemicals, Inc: 1964 (60 years ago)
Global Distribution of Carbene Manufacturers by Country
*Including some distributors, etc.
| Country | Number of Companies | Share (%) |
|---|---|---|
Japan
|
2 | 100.0% |
