We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What Is Salicylaldehyde?

By Vincent Summers
Updated May 21, 2024
Our promise to you
All The Science is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At All The Science, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject-matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

Salicylaldehyde (HO-C6H4-CHO) is the common name for 2-hydroxybenzaldehyde, an oily organic liquid that has the odor of buckwheat. It is a simple derivative of the hexagonal ring compound benzene (C6H6). One of benzene’s hydrogen atoms is replaced by an aldehyde group (-CHO). A hydroxyl group (-OH) replaces another hydrogen atom attached to an adjacent carbon. Thanks in part to these reactive side groups and their “one-two” location on the benzene ring, salicylaldehyde is a powerful tool in chelation chemistry and in ring-generating condensation chemistry.

The most important use of salicylaldehyde involves chelates — molecules that act, as the name suggests, like crab claws. One or more aldehyde or derivative molecules attaches to a target metal atom through coordination bonding, which occurs when both electrons are provided by just one atom. For salicylaldehyde copper chelate, the four oxygen atoms of the two aldehyde molecules symmetrically surround, then attach to, a lone copper atom. Metal chelates, partly because of their stability in unfavorable environments, are used in fertilizers.

In some instances, the chelate itself is not what is commercially desired. Rather, it is the ability to form chelates at the point of use that is valuable. When this is the situation, salicylaldehyde is almost always chemically modified before use. A particular derivative is formed and is designed to be applicable in a very specific situation. One example is salicylaldehyde isonicotinoyl hydrazone, which has been proven capable of reducing dangerous levels in a not uncommon heart malady called catecholamine cardiotoxicity.

Another chelation use of the aldehyde requires reacting it first with hydroxylamine to form salicylaldoxime. This oxime of the aldehyde is practical to the analytical chemist because it generates brilliant and distinct colors in the presence of transition metal ions. Transition metals are those metals whose d-subshell of orbital electrons is incomplete and include such metals as nickel, iron, chromium, copper and cobalt. Insoluble transition metal complexes are formed and are then collected, dried and quantified through appropriate laboratory procedures. A similar titration procedure employs the phenylhydrazone to quantify organometallic reagents.

Other important, non-chelate related organic syntheses using salicylaldehyde include condensation reactions. Condensation reactions combine two or more molecules to form larger, more complex species. One example is the reaction of the aldehyde with ethyl malonate in the presence of other minor reactants to form the aldol condensation product 3-carbethoxycoumarin, a two-ring structure. Not all reactions employing salicylaldehyde create more complex species; some, such as the oxidation to catechol, are simple conversion reactions.

All The Science is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Discussion Comments
All The Science, in your inbox

Our latest articles, guides, and more, delivered daily.

All The Science, in your inbox

Our latest articles, guides, and more, delivered daily.