Shanghai, China – October 22, 2026
5-Bromoindole, CAS 10075-50-0, is a halogenated indole derivative in which bromine is located at the 5-position of the indole framework. It has the molecular formula C8H6BrN, a molecular weight of approximately 196.04 g/mol, and the IUPAC name 5-bromo-1H-indole.
For synthetic chemists, however, its value is not defined only by the presence of bromine. The important feature is that bromine is already installed at a specific position on a pre-formed indole scaffold.
That combination makes 5-Bromoindole useful as a position-defined halogenated intermediate for constructing more complex indole derivatives, particularly when downstream chemistry requires functionalization at C5.
Why the C5 Bromine Matters
The indole framework contains several positions that can be modified during molecular development. In 5-Bromoindole, the bromine atom occupies the C5 position on the benzene portion of the fused ring system.
This positional identity is important.
5-Bromoindole is not interchangeable with 4-Bromoindole, 6-Bromoindole or 7-Bromoindole. Although these compounds belong to the same general chemical family, the bromine atom occupies a different position in each structure.
For a downstream synthesis designed around C5 functionalization, beginning with 5-Bromoindole provides chemists with a defined structural starting point.
The value of the compound can therefore be summarized as:
a pre-formed indole scaffold containing a bromine atom specifically positioned at C5 for further molecular construction.
Bromine as a Synthetic Functional Handle
5-Bromoindole in Suzuki–Miyaura Cross-Coupling
One clear example is Suzuki–Miyaura chemistry, which is widely used to form carbon–carbon bonds between suitable halogenated compounds and organoboron reagents.
A 2020 study on Suzuki–Miyaura coupling used commercially available 5-Bromoindole and phenylboronic acid as a benchmark system while developing a palladium-nanoparticle catalytic method.
From a molecular-design perspective, this example demonstrates the practical role of 5-Bromoindole:
C5–Br → C5–C
The brominated position becomes the site at which a new carbon substituent can be introduced.
This makes 5-Bromoindole relevant when researchers want to prepare 5-substituted indole derivatives without rebuilding the indole nucleus from the beginning.
The exact efficiency of a particular coupling must still be validated for the specific reaction system. A published reaction should be treated as evidence of synthetic utility, not as a guaranteed manufacturing result for every downstream process.
Beyond Suzuki Coupling: Other Routes to C5 Functionalization
The usefulness of the bromine handle is not limited to one type of coupling.
Published research has also demonstrated Sonogashira functionalization of unprotected 5-Bromoindole. In a 2017 Chemical Science study, researchers reacted 5-Bromoindole with phenylacetylene and obtained the corresponding alkynylated derivative, demonstrating that the C5 bromine position could support carbon–carbon bond formation through this different coupling strategy.
A broader review of indole functionalization also describes palladium-catalyzed amination of 5-Bromoindole with amine partners.
More recently, research published in 2026 investigated Buchwald–Hartwig amination of N-protected 5-bromoindole derivatives, producing corresponding 5-amino-functionalized indoles.These examples illustrate an important principle:
5-Bromoindole is useful because its brominated C5 position can provide an entry point to multiple classes of downstream indole derivatives.
The raw material itself should not be described as having the pharmaceutical, biological or photophysical properties of those final derivatives.
Why This Matters in Indole Derivative Development
In fine organic and medicinal-chemistry research, teams often need a series of related compounds in which one position on a core scaffold carries different substituents.
5-Bromoindole can support this type of molecular diversification because the indole framework and C5 substitution position are already established.
Depending on the chosen chemistry, researchers may use the C5 position to introduce:
This makes the material particularly relevant to indole derivative libraries, heterocyclic intermediate development and multistep organic synthesis.
It would still be inaccurate to describe 5-Bromoindole as universally “highly reactive” or to claim that it automatically produces better yields. Its usefulness depends on whether the target route specifically benefits from a C5 brominated indole intermediate.
Physical Identity and Commercial Specification
Reference databases identify 5-Bromoindole as C8H6BrN, MW 196.04 g/mol. Commercial reference data report melting-point values around 88–92°C.
Some external suppliers publish assay values such as 99% or higher for their own grades. Those values belong to those specific commercial products and should not be transferred to Starsky Chemical’s 5-Bromoindole.
For Starsky material, technical users should rely on the current Starsky specification and lot-specific Certificate of Analysis when evaluating assay, impurities or other quality parameters.
This is particularly relevant in coupling chemistry, where impurity profile and material consistency may affect downstream process development.
What Should Technical Teams Evaluate?
When considering 5-Bromoindole as a starting intermediate, the first question is whether the target molecular architecture requires functionalization specifically at C5.
Teams should then confirm the exact material identity:
5-Bromoindole — CAS 10075-50-0
rather than relying only on the general description “bromoindole.”
For repeated R&D or production use, relevant evaluation may include current assay, analytical identity, positional-isomer control where necessary, impurity profile, COA documentation and consistency across qualified lots.
The appropriate specification should ultimately reflect the requirements of the downstream synthesis.
Safety and Documentation
5-Bromoindole should be evaluated using the current SDS for the actual supplied product and applicable internal EHS requirements. Commercial safety documentation for 5-Bromoindole includes skin- and eye-irritation classifications, but supplier-specific SDS information should take precedence over general website content.
Why Choose a C5-Brominated Indole Intermediate?
5-Bromoindole is most useful when a synthetic program requires an indole scaffold with a defined functionalization point at C5.
Its value is therefore not simply that it contains bromine. The C5 bromine provides a chemically useful handle that can participate in downstream transformations while preserving the underlying indole framework.
Published Suzuki–Miyaura, Sonogashira and amination research demonstrates how 5-bromoindole structures can be diversified into more complex derivatives.
For Starsky Chemical, 5-Bromoindole / CAS 10075-50-0 is therefore most appropriately positioned as a halogenated indole intermediate for customers developing position-defined indole derivatives through downstream organic synthesis.
About Us
Shanghai Starsky New Material Co., Ltd. is a combination of R&D, production, and sales. We have been specializing in the import and export of chemical products for more than 12 years. We have served 8,000+ customers in more than 100 countries from all over the world, Also have established long-term cooperative relationship with our customers.
Media ContactCompany Name: Shanghai Starsky New Material Co., Ltd.Contact Person: Media RelationsEmail: Send EmailCountry: ChinaWebsite: https://www.starskychemical.com/
