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1, hydrazone
According to the naming principle of functional groups, the class name "hydrazone" can be added to the name of the corresponding aldehyde or ketone, or it can be named as the derivative of parent hydride (hydrazine) [diazepine (hydrazine) ]NH2NH2 by substitution method.
When it is not the main characteristic group, the prefix "hydrazine group-"can be connected to the name of the parent hydride or the prefix of the parent substituent for naming, and IUPAC—2004 suggests using "hydrazine subunit" as the prefix.
2. Functional groups
In chemistry, "functional group" refers to the combination of specific atoms or atomic groups with specific chemical properties and reaction behaviors in molecules. They are the key parts that determine the properties and reactivity of compounds.
Functional groups can be a combination of one or more atoms, which usually react with other parts of the molecule. They can cause various changes in chemical properties and reactions in molecules, such as acidity and alkalinity, redox, electrophilic, nucleophilic and so on.
Some common functional groups are hydroxyl (-OH), ketone (C=O), carbonyl (C=O), ester (-COO-), amino (-NH2), aldehyde (-CHO), halogen (-Cl, -Br, -I) and so on. Different functional groups play an important role in the properties and chemical reactions of compounds.
Functional group conversion chemists can convert one functional group into another through various chemical reactions, thus synthesizing the target compound. This is one of the common strategies in organic synthesis. For example, alcohols can be converted into aldehydes or ketones by oxidation reaction, and carboxylic acid esters can be converted into acids by hydrolysis reaction.
By identifying and understanding the functional groups in molecules, chemists can predict and explain the properties of compounds, reaction pathways and interactions with other molecules.