ChemistryChapter 21: Organic Synthesis
A Map of School Conversions
Alkene --H2/Ni--> alkane.
Learning objectives
- Explain a map of school conversions in simple chemical language.
- Connect 1. c=c box with 2. oh / c=o / cooh using equations, observations, or trends where needed.
- Answer a short Federal Board question with the correct terms and a clear reason.
Definition
Alkene --H2/Ni--> alkane. Alkene --HBr--> haloalkane. Alkene --steam/H+--> alcohol. Haloalkane --KOH aq--> alcohol. Haloalkane --KOH alc--> alkene. Alcohol --dichromate--> aldehyde/ketone/acid. Alcohol --conc H2SO4--> alkene. Acid + alcohol --H2SO4--> ester. Haloalkane --CN- --> nitrile --hydrolyse--> acid (extra carbon). Meaning: draw the map, then pick a path of two boxes. Alkene -> halogenoalkane -> alcohol -> aldehyde -> acid — backbone map for exams. Count carbons after each synthetic step; silent carbon loss is the most common multi-step mistake.
Important terms
- A MAP OF SCHOOL CONVERSIONS
- Alkene --H2/Ni--> alkane.
- 1. C=C BOX
- In: dehydration or elimination.
- 2. OH / C=O / COOH
- Ox up the hill.
Overview
Hydrocarbons, then oxygen groups:
C=c Box
In: dehydration or elimination. Out: addition (Br2, HBr, H2, H2O). Polymer is a dead-end for further small-molecule steps (school). Nitrile reduction to amine; ester hydrolysis to acid — arrows on revision diagram.
Examples Br2 test · Hydration named · H2/Ni
Oh / C=o / Cooh
Ox up the hill. Reduce down with named hydrides. Ester side path. Carbonate tests the acid. Only use conversions your syllabus allows — question states starting set.
Examples Distil vs reflux · NaBH4 named · Esterify
WHAT — A MAP OF SCHOOL CONVERSIONS
Alkene --H2/Ni--> alkane. Alkene --HBr--> haloalkane. Alkene --steam/H+--> alcohol. Haloalkane --KOH aq--> alcohol. Haloalkane --KOH alc--> alkene. Alcohol --dichromate--> aldehyde/ketone/acid. Alcohol --conc H2SO4--> alkene. Acid + alcohol --H2SO4--> ester. Haloalkane --CN- --> nitrile --hydrolyse--> acid (extra carbon). Meaning: draw the map, then pick a path of two boxes. Alkene -> halogenoalkane -> alcohol -> aldehyde -> acid — backbone map for exams. Count carbons after each synthetic step; silent carbon loss is the most common multi-step mistake.
WHY — Why this topic matters
A MAP OF SCHOOL CONVERSIONS is an independent FBISE learning unit because students must use its definitions, conditions, equations, or trends separately in explanations and calculations.
HOW — How it works
C=C BOX: In: dehydration or elimination. Out: addition (Br2, HBr, H2, H2O). Polymer is a dead-end for further small-molecule steps (school). Nitrile reduction to amine; ester hydrolysis to acid — arrows on revision diagram. Examples: Br2 test; Hydration named; H2/Ni. OH / C=O / COOH: Ox up the hill. Reduce down with named hydrides. Ester side path. Carbonate tests the acid. Only use conversions your syllabus allows — question states starting set. Examples: Distil vs reflux; NaBH4 named; Esterify. Worked two-step: ethene to ethanoic acid. ethene + steam/H+ -> ethanol ethanol reflux dichromate -> ethanoic acid school names only
Worked example
- Worked two-step: ethene to ethanoic acid.
- ethene + steam/H+ -> ethanol
- ethanol reflux dichromate -> ethanoic acid
- school names only
In simple words
Map of syllabus arrows. No extra illicit steps.
Key points
- each arrow is a named reagent
- CN- adds a carbon
- unsaturation hub
- ox state hill
Exam preparation
Exam Focus
Quick revision
Revision Zone
Review the key facts, formulas and checks before you move on.A Map of School Conversions
Sticky Notes · Quick Revision
Core Idea
- Alkene --H2/Ni--> alkane. Alkene --HBr--> haloalkane. Alkene --steam/H+--> alcohol. Haloalkane --KOH aq--> alcohol. Haloalkane --KOH alc--> alkene. Alcohol --dichromate--> aldehyde/ketone/acid. Alcohol --conc H2SO4--> alkene. Acid + alcohol --H2SO4--> ester. Haloalkane --CN- --> nitrile --hydrolyse--> acid (extra carbon). Meaning: draw the map, then pick a path of two boxes. Alkene -> halogenoalkane -> alcohol -> aldehyde -> acid — backbone map for exams. Count carbons after each synthetic step; silent carbon loss is the most common multi-step mistake.
1. C=C BOX
- In: dehydration or elimination. Out: addition (Br2, HBr, H2, H2O). Polymer is a dead-end for further small-molecule steps (school). Nitrile reduction to amine; ester hydrolysis to acid — arrows on revision diagram.
- Br2 test
- Hydration named
- H2/Ni
2. OH / C=O / COOH
- Ox up the hill. Reduce down with named hydrides. Ester side path. Carbonate tests the acid. Only use conversions your syllabus allows — question states starting set.
- Distil vs reflux
- NaBH4 named
- Esterify
Exam Example
- Worked two-step: ethene to ethanoic acid.
- ethene + steam/H+ -> ethanol
- ethanol reflux dichromate -> ethanoic acid
- school names only
Common Misconceptions
- Do not confuse 1. C=C BOX with 2. OH / C=O / COOH; state the difference before giving an example.
- Writing only “each arrow is a named reagent” is not enough. Explain what it means in a complete sentence.
FBISE Exam Check
- Explain a map of school conversions, compare its two main parts, and include the correct chemical evidence.
- Map of syllabus arrows. No extra illicit steps.
60-second revision
- Alkene --H2/Ni--> alkane.
- 1. C=C BOX: In: dehydration or elimination.
- 2. OH / C=O / COOH: Ox up the hill.
- Exam reminder: Worked two-step: ethene to ethanoic acid.
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