Identify the most suitable reagent to carry out the following chemical transformation:

Step-by-step solution

The given chemical transformation involves the oxidation of benzyl alcohol (a primary alcohol) to benzaldehyde (an aldehyde). To stop the oxidation at the aldehyde stage and prevent further oxidation to a carboxylic acid, a mild oxidizing agent must be used. Let us evaluate the given reagents: OsO ₄ (Osmium tetroxide) is typically used for the syn-dihydroxylation of alkenes, not for oxidizing alcohols. HCrO ₄ (Chromic acid) and K ₂ Cr ₂ O ₇ (Potassium dichromate) are strong oxidizing agents. They will oxidize benzy