Organic Chemistry Reagents and Conditions

Flashcards covering organic chemistry functional group transformations, reaction conditions, reagents, synthesis pathways, and analytical tests based on the lecture notes.

What are the reagents and conditions for the chlorination of ethane to chloroethane?

General reaction: $Cl_2$ with UV light at room temperature.

What are the reagents and conditions for the complete combustion of ethane?

Excess oxygen with ignition or heat ($2C_2H_6 + 7O_2 \rightarrow 4CO_2 + 6H_2O$).

What are the reagents and conditions for the bromination of ethene to 1,2-dibromoethane?

$Br_2$ in $CCl_4$ at room temperature in the dark.

What are the reagents and conditions for the hydrogenation of ethene to ethane?

$H_2(g)$ with a Ni catalyst and heat.

What are the reagents and conditions for the complete combustion of ethene?

Excess oxygen with ignition or heat ($C_2H_4 + 3O_2 \rightarrow 2CO_2 + 2H_2O$).

What are the reagents and conditions to convert bromoethane to ethanol via nucleophilic substitution?

$NaOH(aq)$ heated under reflux.

What are the reagents and conditions for the elimination of bromoethane to ethene?

NaOH in ethanol with heat.

What are the reagents and conditions for the complete combustion of ethanol?

Excess oxygen with ignition or heat ($C_2H_5OH + 3O_2 \rightarrow 2CO_2 + 3H_2O$).

What are the reagents and conditions to oxidise ethanol fully to ethanoic acid using potassium dichromate?

$K_2Cr_2O_7(aq) + \text{dilute } H_2SO_4$ heated under reflux.

What are the reagents and conditions to oxidise ethanol fully to ethanoic acid using potassium manganate(VII)?

$KMnO_4(aq) + \text{dilute } H_2SO_4$ heated under reflux.

What are the reagents and conditions for the dehydration of ethanol to ethene under the current syllabus?

Concentrated $H_3PO_4$ catalyst with heat.

What are the reagents and conditions for reducing ethanal to ethanol using hydride reduction?

1. $LiAlH_4$ in dry ether; 2. aqueous work-up.

What are the reagents and conditions for reducing ethanal to ethanol using catalytic hydrogenation?

$H_2(g)$ with a Ni catalyst and heat.

What are the reagents and conditions for reducing propanone to propan-2-ol using lithium aluminium hydride?

1. $LiAlH_4$ in dry ether; 2. aqueous work-up.

What are the reagents and conditions for reducing propanone to propan-2-ol using catalytic hydrogenation?

$H_2(g)$ with a Ni catalyst and heat.

What are the reagents and conditions to oxidise ethanal to ethanoic acid using potassium dichromate?

$K_2Cr_2O_7(aq) + \text{dilute } H_2SO_4$ heated under reflux.

What are the reagents and conditions to oxidise ethanal to ethanoic acid using potassium manganate(VII)?

$KMnO_4(aq) + \text{dilute } H_2SO_4$ heated under reflux.

What are the reagents and conditions for salt formation between ethanoic acid and sodium hydroxide?

$NaOH(aq)$ at room temperature.

What are the reagents and conditions for the reaction of ethanoic acid with sodium carbonate?

$Na_2CO_3(aq)$ at room temperature ($2CH_3COOH + Na_2CO_3 \rightarrow 2CH_3COONa + CO_2 + H_2O$).

What are the reagents and conditions for the esterification of ethanoic acid with ethanol?

Concentrated $H_2SO_4$ catalyst heated under reflux.

What are the reagents and conditions to form N-ethylethanamide from ethanoic acid and ethylamine?

DCC under mild or room-temperature conditions.

What are the reagents and conditions for the acidic hydrolysis of ethyl ethanoate?

Dilute $HCl(aq)$ heated under reflux.

What are the reagents and conditions for the alkaline hydrolysis of ethyl ethanoate?

$NaOH(aq)$ heated under reflux.

What are the reagents and conditions for the acidic hydrolysis of ethanamide?

Dilute $HCl(aq)$ heated under reflux (yielding ethanoic acid and ammonium chloride).

What are the reagents and conditions for the alkaline hydrolysis of ethanamide?

$NaOH(aq)$ heated under reflux (yielding sodium ethanoate and ammonia).

What are the reagents and conditions for the acidic hydrolysis of N-ethylethanamide?

Dilute $HCl(aq)$ heated under reflux (yielding ethanoic acid and ethylammonium chloride).

What are the reagents and conditions for the alkaline hydrolysis of N-ethylethanamide?

$NaOH(aq)$ heated under reflux (yielding sodium ethanoate and ethylamine).

What are the reagents and conditions to convert ethylamine to ethylammonium chloride?

$HCl(aq)$ at room temperature.

What are the reagents and conditions for the acidic hydrolysis of proteins?

Dilute $HCl(aq)$ heated under reflux (yielding amino acids in protonated forms).

What are the reagents and conditions for the alkaline hydrolysis of proteins?

$NaOH(aq)$ heated under reflux (yielding amino-acid carboxylate salts).

What are the reagents and conditions for the acidic hydrolysis of a polyester?

Dilute $HCl(aq)$ heated under reflux (yielding carboxylic acid groups and alcohol groups).

What are the reagents and conditions for the alkaline hydrolysis of a polyester?

$NaOH(aq)$ heated under reflux (yielding carboxylate groups and alcohol groups).

What are the reagents and conditions for the acidic hydrolysis of a polyamide?

Dilute $HCl(aq)$ heated under reflux (yielding carboxylic acid groups and ammonium groups).

What are the reagents and conditions for the alkaline hydrolysis of a polyamide?

$NaOH(aq)$ heated under reflux (yielding carboxylate groups and amine groups).

Which room-temperature colour test distinguishes ethene from ethane?

$Br_2$ in $CCl_4$ at room temperature in the dark (ethene decolourises reddish-brown bromine, while ethane gives no reaction).

Which chemical test distinguishes ethanal from propanone?

$K_2Cr_2O_7(aq) + \text{dilute } H_2SO_4$ heated under reflux (ethanal turns orange dichromate green; propanone leaves it orange).

Which reagent gives effervescence with ethanoic acid but not with ethanol?

$Na_2CO_3(aq)$ at room temperature (effervescence due to $CO_2$ release).

What are the reagents and conditions to test for an unsubstituted amide such as ethanamide?

$NaOH(aq)$ heated under reflux; the evolved $NH_3$ gas turns damp red litmus blue.

For bromoethane, which NaOH solvent choices yield an alcohol first and an alkene second?

Water for substitution first ($NaOH(aq)$), followed by ethanol for elimination second (NaOH in ethanol).

Which catalyst pair converts ethanol to ethene first and then to an ester with ethanoic acid second?

Concentrated $H_3PO_4$ for dehydration first, then concentrated $H_2SO_4$ for esterification second.

Which solvent is suitable for $LiAlH_4$ during carbonyl reduction?

Dry ether (because $LiAlH_4$ reacts violently with water and alcohols).

What happens when propanone is heated with acidified $K_2Cr_2O_7$?

No oxidation occurs; the orange colour remains.

Will hot aqueous NaOH hydrolyse the C-C backbone of poly(ethene)?

No, because poly(ethene) has no hydrolysable ester or amide links.

What are the reagents and conditions for the two-step synthesis of bromoethane to ethanol to ethanoic acid?

1. $NaOH(aq)$, heat; 2. acidified $K_2Cr_2O_7$, reflux.

What are the reagents and conditions for the two-step synthesis of bromoethane to ethene to ethane?

1. NaOH in ethanol, heat; 2. $H_2(g)$, Ni catalyst, heat.

What are the reagents and conditions for the two-step synthesis of ethanal to ethanol to ethyl ethanoate?

1. $H_2(g)$, Ni catalyst, heat; 2. ethanoic acid, concentrated $H_2SO_4$, heat.

What are the reagents and conditions to convert ethyl ethanoate to sodium ethanoate and then to ethanoic acid?

1. $NaOH(aq)$, reflux; 2. cool, then add dilute $HCl$.

What are the conditions for the controlled oxidation of ethanol to ethanal, stopping before carboxylic acid formation?

Acidified $K_2Cr_2O_7$; warm and distil ethanal immediately as it forms.

What are the older-note conditions for the dehydration of ethanol using sulfuric acid?

Excess concentrated $H_2SO_4$ with strong heating ($\sim 170\,^\circ\text{C}$).

What are the conditions for dehydrating ethanol vapour over a solid catalyst?

Pass vapour over hot $Al_2O_3$ ($\sim 350\,^\circ\text{C}$).

What are the reagents and conditions to convert ethene to 2-bromoethan-1-ol as the major product?

$Br_2(aq)$ at room temperature.

What sequence is used to test for the halide released from bromoethane?

Heat with $NaOH(aq)$; cool; add dilute $HNO_3$; then add $AgNO_3(aq)$ (a cream $AgBr$ precipitate forms).

What alternative one-step test can detect the halogen in bromoethane?

Ethanolic silver nitrate heated with shaking.

What conditions are required for the catalytic cracking of alkanes (such as butane to ethane and ethene)?

Vaporise and pass over a hot silica/alumina catalyst.

What oxygen supply conditions lead to incomplete hydrocarbon combustion?

Limited oxygen with ignition or heat (producing $CO$ and/or soot/carbon and water).

What reagents and conditions are used to convert ethanoic acid to ethanamide using a coupling agent?

Ammonia with DCC under mild or room-temperature conditions.