CARBOXYLIC ACID, DERIVATIVES

3 compounds derived from carboxylic acids and how theyre related by

anhydride, ester, amide. related by loss of h2o

anhydride

2 carbonyl groups bonded to same oxygen + drawing

types of anhydrides

symmetrical (2 identical acyl groups), mixed (2 different acyl groups)

ester

carbonyl group bonded to OR group (R group alkyl/aryl)

aryl

aromatic ring

what is a cyclic ester called

lactone

ending of ester

oate

amide

carbonyl group bonded to nitrogen

reminder for naming amide

drop oic acid from iupac name/ic acid from common name then add amide

what if amide is bonded to alkyl/aryl group

show location on nitrogen via 'N' or 2 by N, N,di

cyclic amide is called

lactam

penicillin and cephalosporin is referred to as

beta lactam antibiotic

fatty acids

long chain carboxylic acids from animal fat/vegetable oil/phospholipid/biological membrane. 500 isolated from various cell. 12/20 carbons in unbranched chain.

which isomer predominates in unsaturated fatty acids

cis. trans is rare

how is ester formed

carboxyl + alcohol under sulfuric acid

melting point of unsaturated fatty acids

lower than saturated

saturated fatty acids are __ at room temp + why

solid. minimizes london dispersion forces

unsaturated fatty acids are __ at room temp + why

liquids. cis double bond interrupts regular hydrocarbon chain

tallow

insoluble triglyceride layer on top. solid fat (from cattle) melted with steam

triglycerides are

triesters of glycerol

how is soap prepared

boil triglyceride with NaOH. undergoes saponification. boiling with KOH gives potassium soap

describe micelles

hydrophobic tail inside, hydrophilic head outside

what happens when micelle gets dirt

mixed in water, nonpolar hydrocarbon inner part dissolves nonpolar substances

natural soap + hard water

water INSOLUBLE salts

what does hard water contain

ca2+, mg2+, fe3+

how do detergents avoid forming scum (insoluble precipitate) from hard water + soap

sulfonate group (so3) replaces carboxylate co2 group

common additives of detergents

foam stabilizer, bleach, optical brightener

acidity of carboxylic acids

weak acids. Ka 4/5 to 10, pKa 4 to 5

what increases acidity of carboxylic acids

substituents w high electronegativity e.g. OH, Cl, NH3+

form of carboxylic acid when carboxylic acid dissolves in aqueous solution depends on

pH of solution

carboxylic acid + NaOH,KOH/strong base, ammonia, amine

water soluble salt

carboxylic acid + sidum bi/carbonate

water soluble sodium salt + carbonic acid (carbonic acid splits to co2 + h2o, evolve as gas)

what are carboxylic acids resistant to

moderate heat. melt/boil without decarboxylation, except for carbonyl group beta to the COOH group

common preparation of amide

anhydride + amine

3 representations of carboxyl group

diagrams of derivatives

structure of common agents in detergents

beta carbon diagram

example of decarboxylation diagram

physical properties of carboxyl group-

3 polar covalent bonds, C-O, C=O, O-H

physical properties of carboxylic acids + why

1. high bp than other types due to: polarity, hydrogen bonding between carboxyl groups creates dimer behaving as high molecular weight compound

2. soluble than other types

describe soap composition

1. sodium/potassium salt of fatty acids

2. tallow + palm oil (triglyceride)

describe what happens during esterification

1. alcohol adds to carbonyl group of carboxylic acid

2. forms tetrahedral carbonyl

3. ^ loses water to give ester

describe decarboxylation

• loss of co2 from carboxyl group

• carboxylic acids heated to high temps

• electrons redistribute cyclically followed by keto enol tautomerism

describe preparation of amide (carboxylic acid + amine)

• carboxylic acid + amine

• remove OH from carboxylic acid

• remove H from amine

• forms ammonium salt

• salt heated to high temp to eliminate water = amide