En La Sala De Un Hospital Nacio Simon

Written by Julián Pérez
Updated at: 23 February 2026

“En la sala de un hospital nació Simón” is a popular mnemonic phrase in Spanish used to remember the order of reactivity of alcohols with hydrogen halides (HX) in substitution reactions. Essentially, it helps predict which type of alcohol – primary, secondary, or tertiary – will react fastest. This is vital for organic chemistry labs when planning or predicting the outcome of reactions.

Understanding Reactivity Order

The phrase translates to "In the hospital room, Simon was born." Each word represents a different type of alcohol:

En – Not relevant, filler word.
La – Not relevant, filler word.
Sala – Secundario (Secondary Alcohol)
De – Not relevant, filler word.
Un – Not relevant, filler word.
Hospital – Not relevant, filler word.
Nació – Primario (Primary Alcohol)
Simon – Tertiary Alcohol

Therefore, the order of reactivity is: Tertiary > Secondary > Primary. This means tertiary alcohols react fastest with HX, followed by secondary, and then primary alcohols react the slowest (or sometimes not at all under certain conditions).

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Applying the Rule: Step-by-Step

Here's how to use "En la sala de un hospital nació Simón":

Identify the Alcohol Type: Look at the carbon atom bonded to the -OH group.
- Primary: The carbon is bonded to only one other carbon.
- Secondary: The carbon is bonded to two other carbons.
- Tertiary: The carbon is bonded to three other carbons.
Predict Reactivity: Using "En la sala de un hospital nació Simón", determine which alcohol will react faster based on its type. Tertiary alcohols will react the quickest.

Example

Consider these alcohols reacting with HCl:

Si sabes que pasó en la sala de un hospital a las 9:43 en el verano del

2-methyl-2-propanol (Tertiary)
2-propanol (Secondary)
1-propanol (Primary)

Based on "En la sala de un hospital nació Simón", we predict that 2-methyl-2-propanol (tertiary) will react the fastest with HCl. 2-propanol (secondary) will react slower, and 1-propanol (primary) will react the slowest.

This simple mnemonic provides a quick and easy way to remember the relative reactivities, crucial for success in predicting reaction outcomes.