Cl*Mg

Do you mean Grignard reagents formed from an alkyl/aryl chloride with magnesium (R-Cl + Mg → RMgCl)? If yes, here’s a quick refresher you can use for exams. Key ideas (Grignard reagents RMgX, with X = Cl in your case) - Preparation: R-Cl + Mg in dry ether (diethyl ether or THF) under inert atmosphere. Initiation can be slow; sometimes small activators (I2, 1,2-dibromoethane) are used. - Solvent role: Ethers stabilize Mg via coordination (O-lone pairs on ethers to Mg). - Reactivity order: RI > RBr > RCl (RCl is the least reactive; slower initiation and consumption). - Workup: RMgX + H2O or (NH4)Cl → RH + Mg(OH)X; RMgX + CO2 → RCO2MgX, then acidic workup gives carboxylic acid; RMgX + aldehyde/ketone → secondary/ tertiary alcohol after hydrolysis. - Typical reactions (high-yield exam concepts): - With formaldehyde (H2C=O): R-CH2OH after workup (primary alcohol with one extra carbon). - With aldehydes: RMgX adds to give secondary alcohols after workup. - With ketones: RMgX adds to give tertiary alcohols after workup. - With CO2: carboxylic acid after acidic workup (R-CO2H). - With epoxides: nucleophilic opening to give alcohols with chain extension (R–CH2–CH2OH type product, depending on conditions). A quick example - Ethyl chloride (EtCl) + Mg → EtMgCl (in dry THF or diethyl ether) - EtMgCl + CO2 → EtCO2MgCl - Acid workup → propionic acid (EtCO2H) If you meant something else by "Cl*Mg" (for example a different notation, or a specific intermediate), please clarify and I’ll tailor the explanation. Do you want me to work through a concrete exam-style problem? If so, tell me the exact setup (e.g., which R-Cl and which reagent or which product you need).