Acyl chlorides | Hydrolysis and distinguishing tests | A Level H2 Chem | Making Sense Chem скачать в хорошем качестве

Acyl chlorides | Hydrolysis and distinguishing tests | A Level H2 Chem | Making Sense Chem

A LEVEL CHEMISTRY!! music by: Zight - Paradise - https://thmatc.co/?l=3B73F710 In today's video, we will be talking about the derivatives of carboxylic acids and esters! 0:00 Introduction 0:07 Hydrolysis of acyl chloride (RCOCl), alkyl chlorides (R-Cl) and aryl chlorides (Ar-Cl) 7:23 Test to distinguish between RCOCl, R-Cl, Ar-Cl 10:15 Introduction to esters 11:11 Nomenclature of esters 13:10 Let’s practice naming esters! 16:01 Preparation of esters 20:36 Chemical properties of esters Hydrolysis of acyl chloride (RCOCl), alkyl chlorides (R-Cl) and aryl chlorides (Ar-Cl) Hydrolysis: attack of an electrophile by the nucleophile H₂O or OH⁻ (lone pair of e⁻ on O) Most electrophilic will be most susceptible to nucleophilic substitution Ease of hydrolysis in ascending order: aryl chloride, alkyl chloride, acyl chloride 1) Acyl chloride undergo hydrolysis readily with water Carbonyl carbon is very electron-deficient (𝛅+) as it is bonded to two strongly electronegative atoms (O and Cl) Attract nucleophiles more strongly 2) Alkyl chlorides undergo hydrolysis with OH⁻, heat Carbon attached to Cl is less electron-deficient as it is only bonded to 1 electronegative atom (Cl) Stronger nucleophile (OH⁻ ) and harsher condition (heating) is required for hydrolysis to occur. Ease of hydrolysis in ascending order: C-F, C-Cl, C-Br, C-I Atomic size increases, orbitals of the halogens more diffused = decreased extent of orbital overlap with carbon = C-X weaker = easier hydrolysis 3) Aryl chloride DO NOT undergo hydrolysis at all conditions C of the C-Cl is part of the electron-rich benzene, hence repelling nucleophiles p orbital of chlorine overlaps with adjacent 𝝅 electron cloud of benzene ring, allowing delocalisation of its electron pair = partial double bond character NOTE: OH⁻ is a stronger Nu⁻ due to negative charge Test to distinguish between RCOCl, R-Cl, Ar-Cl: Reaction with aq/ethanolic AgNO₃ (H2O in aq medium act as nucleophile to substitute Cl) White ppt of AgCl observed immediately with acyl chloride No immediate ppt but only observed when heated with AgNO₃ (aq) for alkyl chloride No ppt observed even when heated with AgNO₃ (aq) Introduction to esters: Sweet smelling, colourless liquid Neutral Lower boiling point than carboxylic acids since it is unable to form hydrogen bonds between molecules Nomenclature of esters: First name the alkyl group attached to the singly-bonded oxygen (this represents the alcohol group) Name the carboxylate salt of the parent carboxylic acid Name of alcohol on the left, name of carboxylic acid on the right Preparation of esters: 1) Condensation (nucleophilic acyl substitution) Reagent and condition : RCOOH with a few drops of conc. H₂SO₄ (dehydrating agent), heat, OR RCOCl, r.t.p Using RCOOH is reversible while using ROCL is irreversible (higher yield) 2) Condensation (nucleophilic acyl substitution) Reagent: acyl chloride, R-COCL Condition: r.t.p Overlap of p orbitals of O and benzene ring = lone pair on oxygen is delocalised into 𝝅 electron cloud of the benzene ring = less available for donation Chemical properties of esters: Carbon atom is electron-deficient since it is bonded to 2 electronegative oxygen atoms Esters are ELECTROPHILES and undergo nucleophilic substitution reaction Chemical reactions of RCOC Looking for free chemistry resources? Vist our website at: https://www.makingsense-sg.com/free-t... to view other learning resources (content videos + free resources). Follow us on: Youtube - Making Sense Tuition Centre Tik tok - @makingsensechemistry Instagram - @makingsensechemistry Facebook - Making Sense, Singapore's Leading Chemistry Tuition The Best Chemistry tuition! #indigoeducationgroup #bestchemistrytuition  #makingsensechemistry #learningisfun #videolessons #educationalvideos #easyandfunlearning #esters #acylchlorides #hydrolysisreaction #chemicalproperties #chemicalreactions