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Dana W. Mayo holds the Charles Weston Pickard Research Professor of Chemistry Chair at Bowdoin College.During the summers of 1960-1971 he co-directed with Professor R.C. Lord one-week Summer Courses on the Technique and Applications of Infrared Spectroscopy at MIT. From 1972-81 he continued to co-direct these programs at Bowdoin College and became Director in 1982.
Ronald M. Pike is the author of Microscale Organic Laboratory with Multistep and Multiscale Syntheses, Binder Ready Version, 6th Edition, published by Wiley.
David C. Forbes is the author of Microscale Organic Laboratory with Multistep and Multiscale Syntheses, Binder Ready Version, 6th Edition, published by Wiley.
The Organic Chemistry Laboratory 4
Chapter 2 SAFETY 5
Making the Laboratory a Safer Place 5
Nature of Hazards 5
Reduction of Risks 6
Precautionary Measures 7
Thinking About the Risks In Using Chemicals 8
Disposal of Chemicals 8
Material Safety Data Sheets 9
Alternate Sources of Information 12
Estimating Risks from Vapors 13
Microwave Safety 14
Concluding Thoughts 15
General Safety References 16
Chapter 3 INTRODUCTION TO MICROSCALE ORGANIC LABORATORY EQUIPMENT AND TECHNIQUES 18
Microglassware Equipment 19
Standard Taper Joints 19
Conical Vials 20
Condensers 20
Distillation Heads 20
Recrystallization Tubes 20
Miscellaneous Items 20
Gas Chromatographic Fraction Collection Items 21
Standard Experimental Apparatus 21
Heating and Stirring Arrangements 21
Sand Bath Technique—Hot Plate Calibration 21
Metal Heat-Transfer Devices 22
Stirring 22
Reflux Apparatus 23
Distillation Apparatus 24
Moisture-Protected Reaction Apparatus 25
Specialized Pieces of Equipment 26
Microwave Heating as a Tool for Organic Chemistry 27
Introduction 27
Applications 32
Equipment Available 34
Experimental Protocols 35
Microscale Laws 35
Rules of the Trade for Handling Organic Materials at the Microscale Level 35
Rules for Working with Liquids at the Microscale Level 36
Rules for Working with Solids at the Microscale Level 39
The Laboratory Notebook 40
Example of a Laboratory Notebook Entry 41
Calculating Yields 42
Chapter 4 DETERMINATION OF PHYSICAL PROPERTIES 45
Liquids 46
Ultramicro Boiling Point 46
Density 50
Solids 51
Melting Points 51
Chapter 5 MICROSCALE LABORATORY TECHNIQUES 55
TECHNIQUE 1 Gas Chromatography 55
GC Instrumentation 56
TECHNIQUE 2 Simple Distillation 61
TECHNIQUE 3 Fractional Distillation 64
TECHNIQUE 4 Solvent Extraction 67
Intermolecular Properties: Solubility 67
Partition (or Distribution) Coefficient 70
Extraction 72
Solid–Liquid Extraction 79
Drying Agents 80
Solid-Phase Extraction 83
TECHNIQUE 5 Crystallization 85
General Crystallization Procedure 85
Simple Crystallization 87
Filtration Techniques 88
TECHNIQUE 6 Chromatography 92
Column, Flash, High-Performance Liquid, and Thin-Layer Chromatography 92
Column Chromatography 92
Flash Chromatography 95
Thin-Layer Chromatography 97
Paper Chromatography 99
High-Performance Liquid Chromatography 100
TECHNIQUE 6B Concentration of Solutions 101
Distillation 102
Evaporation with Nitrogen Gas 102
Removal of Solvent Under Reduced Pressure 102
TECHNIQUE 7 Collection or Control of Gaseous Products 105
Water-Insoluble Gases 105
Trapping Byproduct Gases 106
TECHNIQUE 8 Measurement of Specific Rotation 108
Theory 108
The Polarimeter 109
TECHNIQUE 9 Sublimation 111
Sublimation Theory 112
Experimental Setup 113
Precautions 113
Chapter 6 MICROSCALE ORGANIC LABORATORY EXPERIMENTS 115
EXPERIMENT 1 Getting to Know You: Measurement of Physical Properties 116
Discussion 117
Experimental Procedure 118
Melting Point 118
EXPERIMENT 2 The Separation of a 25-L Mixture of Heptanal (bp 153 C) and Cyclohexanol (bp 160 C) by Gas Chromatography 123
Discussion 123
Collection Yield 124
Collection Yield 125
Components 126
Experimental Procedure 126
EXPERIMENT 3 Distillation 129
Experiment 3A Simple Distillation at the Semimicroscale
Level: Separation of Ethyl Acetate from trans-1,2-Dibenzoylethylene 130
Discussion 130
Components 130
Experimental Procedure 131
Experiment 3B Fractional Semimicroscale Distillation: Separation of Hexane and Toluene 132
Discussion 133
Components 133
Experimental Procedure 133
Experiment 3C Fractional Semimicroscale Distillation: Separation of 2-Methylpentane and Cyclohexane Using a Spinning-Band Column 135
Discussion 135
Components 136
Experimental Procedure 136
Experiment 3D Fractional Semimicroscale Distillation: The Separation of 2-Methylpentane and Cyclohexane Using a Spinning Band in a Hickman–Hinkle Still 138
Discussion 139
Components 139
Experimental Procedure 139
EXPERIMENT 4 Solvent Extraction 141
Experiment 4A Determination of Partition Coefficient for the System Benzoic Acid, Methylene Chloride, and Water 141
Discussion 141
Components 144
Experimental Procedure 144
Experiment 4B Solvent Extraction I: The System; Benzoic Acid, Methylene Chloride, and 10% Sodium Bicarbonate Solution; An Example of Acid–Base Extraction Techniques 146
Reaction 146
Discussion 146
Experimental Procedure 146
Experiment 4C Solvent Extraction II: A Three-Component Mixture; An Example of the Separation of an Acid, a Base, and a Neutral Substance 147
Discussion 147
Components 148
Experimental Procedure 148
EXPERIMENT 5 Reduction of Ketones Using a Metal Hydride Reagent: Cyclohexanol and cis- and trans-4-tert-Butylcyclohexanol 151
Reaction (Experiment [5A]) 151
Discussion 152
Experiment 5A Cyclohexanol 153
Experimental Procedure 153
Experiment 5B cis- and trans-4-tert-Butylcyclohexanol 158
Reaction 158
Experimental Procedure 158
EXPERIMENT 6 Photochemical Isomerization of an Alkene: cis-1,2-Dibenzoylethylene 163
Biologically Important Photochemical Reactions 164
Reaction 165
Discussion 166
Experiment 6A Purification of trans-1,2-Dibenzoylethylene 166
Experimental Procedure 166
Experiment 6B Isomerization of an Alkene: Thin-Layer Chromatographic Analysis 167
Experimental Procedure 167
Experiment 6C Isomerization of an Alkene: Nuclear Magnetic Resonance Analysis 173
Experimental Procedure 173
EXPERIMENT 7 The Cannizzaro Reaction with 4-Chlorobenzaldehyde: 4-Chlorobenzoic Acid and 4-Chlorobenzyl Alcohol 174
Reaction 176
Discussion 176
Experimental Procedure 177
Experiment 7-1 4-Chlorobenzoic Acid and 4-Chlorobenzyl Alcohol: Preparation Using a Monomode Microwave Apparatus 184
Experimental Procedure 184
Experiment 7-2 4-Chlorobenzoic Acid and
4-Chlorobenzyl Alcohol: Preparation Using a Multimode Microwave Apparatus 185
Experimental Procedure 185
EXPERIMENT 8 The Esterification Reaction: Ethyl Laurate, Isopentyl Acetate, and the Use of Acidic Resins 188
Reaction 188
Discussion 189
Lipids 190
Experiment 8A Ethyl Laurate 199
Reaction 199
Experimental Procedure 199
Experiment 8B Isopentyl Acetate: Semimicroscale Preparation 201
Reaction 201
Experimental Procedure 201
Experiment 8B-1 Isopentyl Acetate: Preparation Using a Monomode Microwave Apparatus 203
Experimental Procedure 203
Experiment 8B-2 Isopentyl Acetate: Preparation Using a Multimode Microwave Apparatus 205
Experimental Procedure 205
Experiment 8C Esterification by Use of Acidic Resins: Semimicroscale Preparations 206
Reaction 207
Experimental Procedure 207
EXPERIMENT 9 The E1 Elimination Reaction: Dehydration of 2-Butanol to Yield 1-Butene, trans-2-Butene, and cis-2-Butene 209
The Development of Carbocation Theory 210
Reaction 211
Discussion 212
Experimental Procedure 215
EXPERIMENT 10 The E2 Elimination Reaction: Dehydrohalogenation of 2-Bromobutane to Yield 1-Butene, trans-2-Butene, and cis-2-Butene 217
Reaction 218
Discussion 218
Experimental Procedure 220
EXPERIMENT 11 The Isolation of Natural Products 224
Experiment 11A Isolation and Characterization of an Optically Active Natural Product: Usnic Acid 224
Lichens and Natural Products 225
Discussion 227
Experimental Procedure 227
Experiment 11B Isolation and Characterization of a Natural Product: Caffeine and Caffeine 5-Nitrosalicylate 229
Alkaloids 230
The Classification of Alkaloids 230
Discussion 231
Experimental Procedure 233
Derivative: Caffeine 5-Nitrosalicylate 235
Experimental Procedure 236
Experiment 11C Isolation of a Natural Product by Steam Distillation: Cinnamaldehyde from Cinnamon 238
Essential Oils 239
Discussion 241
Component 242
Experimental Procedure 242
EXPERIMENT 12 Reductive Catalytic Hydrogenation of an Alkene: Octane 244
Reaction 245
Discussion 245
Experimental Procedure 247
EXPERIMENT 13 Hydroboration–Oxidation of an Alkene: Octanol 250
Reaction 251
Discussion 251
Experimental Procedure 254
EXPERIMENT 14 Diels–Alder Reaction: 4-Cyclohexenecis-1,2-dicarboxylic Acid Anhydride 257
Reaction 258
Discussion 259
Experimental Procedure 261
Optional Semimicroscale Preparation 266
EXPERIMENT 15 Diels–Alder Reaction: 9,10-Dihydroanthracene-9,10-,-succinic Acid Anhydride 269
Reaction 269
Discussion 270
Experimental Procedure 271
Optional Semimicroscale Preparations 272
Experiment 15-1 9,10-Dihydroanthracene-9,10-,-succinic Acid Anhydride: Preparation Using a Monomode Microwave Apparatus 273
Experimental Procedure 273
Experiment 15-2 9,10-Dihydroanthracene-9,10-,-succinic Acid Anhydride: Preparation Using a Multimode Microwave Apparatus 274
Experimental Procedure 274
EXPERIMENT 16 Grignard Reaction with a Ketone: Triphenylmethanol 275
Reaction 276
Discussion 277
Experimental Procedure 279
EXPERIMENT 17 Grignard Reaction with an Aldehyde: 4-Methyl-3-heptanol 284
Reaction 284
Discussion 284
Experimental Procedure 285
EXPERIMENT 18 The Perkin Reaction: Condensation of Rhodanine with an Aromatic Aldehyde to Yield o-Chlorobenzylidene Rhodanine 289
Reaction 290
Discussion 291
Experimental Procedure 292
Optional Semimicroscale Preparation 293
EXPERIMENT 19 Alkene Preparation by the
Wittig Reaction: (E)-Stilbene; Methylene-4-tertbutylcyclohexane; and trans-9-(2-Phenylethenyl) anthracene 294
Reaction 296
Discussion 296
Experiment 19A (E)-Stilbene by the “Instant Ylide” Method 299
Reaction 299
Experimental Procedure 300
Experiment 19B (E)-Stilbene by the Horner–Wadsworth–Emmons Reaction 302
Reaction 302
Experimental Procedure 302
Experiment 19C Methylene-4-tert-butylcyclohexane 303
Reaction 303
Experimental Procedure 304
Experiment 19D trans-9-(2-Phenylethenyl) anthracene 306
Reaction 306
Experimental Procedure 306
EXPERIMENT 20 Aldol Reaction: Dibenzalacetone 309
Reaction 309
Discussion 310
Experimental Procedure 311
Optional Semimicroscale Preparation 316
EXPERIMENT 21 Quantitative Analysis of Grignard Reagents: 1-Methylbutylmagnesium Bromide and Phenylmagnesium Bromide 317
Reaction 318
Discussion 318
Experimental Procedure 319
EXPERIMENT 22 Williamson Synthesis of Ethers 321
Reaction 321
Discussion 322
Experiment 22A Propyl p-Tolyl Ether 323
Experimental Procedure 323
Optional Macroscale Preparation 324
Experiment 22B Methyl p-Ethylphenyl Ether 327
Reaction 327
Experimental Procedure 327
Optional Semimicroscale and Macroscale
Preparations 329
Experiment 22C Butyl p-Nitrophenyl Ether: Preparation Using a Monomode Microwave Apparatus 332
Reaction 332
Experimental Procedure 332
Experiment 22D Butyl p-Nitrophenyl Ether: Preparation Using a Multimode Microwave Apparatus 334
Reaction 334
Experimental Procedure 334
EXPERIMENT 23 Amide Synthesis: Acetanilide and N,N’-Diacetyl-1,4-phenylenediamine 338
Reaction 338
Discussion 339
Experiment 23A Acetanilide 341
Experimental Procedure 341
Optional Semimicroscale Preparation 342
Experiment 23B N,N’-Diacetyl-1,4-phenylenediamine 343
Reaction 343
Experimental Procedure 343
EXPERIMENT 24 Imide Synthesis: N-Phenylmaleimide 346
Reaction 346
Discussion 347
Experiment 24A Maleanilic Acid 348
Experimental Procedure 348
Reaction 348
Experiment 24B N-Phenylmaleimide 349
Reaction 349
Experimental Procedure 350
EXPERIMENT 25 Synthesis of Cyclic Carboxylic Acid Anhydrides: Succinic Anhydride and Phthalic Anhydride 352
Reaction 352
Discussion 352
Experiment 25A Succinic Anhydride 354
Experimental Procedure 354
Experiment 25B Phthalic Anhydride 355
Reaction 355
Experimental Procedure 355
EXPERIMENT 26 Diazonium Coupling Reaction: Methyl Red 356
Reaction 357
Discussion 357
Experimental Procedure 359
EXPERIMENT 27 Friedel–Crafts Acylation: Acetylferrocene and Diacetylferrocene 361
Reaction 362
Discussion 362
Experimental Procedure 364
EXPERIMENT 28 Halogenation: Electrophilic Aromatic Substitution to Yield 4-Bromoacetanilide 368
Reaction 368
Discussion 369
Experimental Procedure 369
EXPERIMENT 29 Nitration: 2,5-Dichloronitrobenzene; N,N’-Diacetyl-2,3-dinitro-1,4-phenylenediamine; 5-Nitrosalicylic Acid; and 2- and 4-Nitrophenol 373
General Reaction 374
Discussion 374
Semimicroscale Preparation of Anhydrous Nitric Acid 375
Experimental Procedure 376
Experiment 29A 2,5-Dichloronitrobenzene 376
Reaction 376
Experimental Procedure 377
Experiment 29B N,N-Diacetyl-2,3-dinitro-1,4-phenylenediamine 378
Reaction 378
Experimental Procedure 378
Experiment 29C 5-Nitrosalicylic Acid 379
Reaction 379
Experimental Procedure 380
Experiment 29D 2- and 4-Nitrophenol 381
Reaction 381
Experimental Procedure 381
EXPERIMENT 30 Nucleophilic Aromatic Substitution: 2,4-Dinitrophenylthiocyanate 384
Reaction 385
Discussion 385
Experimental Procedure 386
Experiment 30-1 2,4-Dinitrophenylthiocyanate: Preparation Using a Monomode Microwave Apparatus 387
Experimental Procedure 387
Experiment 30-2 2,4-Dinitrophenylthiocyanate: Preparation Using a Multimode Microwave Apparatus 388
Experimental Procedure 388
EXPERIMENT 31 Halogenation Using
N-Bromosuccinimide: 9-Bromoanthracene 390
Reaction 390
Discussion 391
Initiation Step 391
Propagation Step 391
Experimental Procedure 392
EXPERIMENT 32 Hypochlorite Oxidation of an Alcohol: Cyclohexanone 394
Reaction 394
Discussion 394
Experimental Procedure 395
EXPERIMENT 33 Chromium Trioxide–Resin or Hypochlorite Oxidation of an Alcohol: 9-Fluorenone 398
Experiment 33A 9-Fluorenone: CrO3 Oxidation of 9-Fluorenol 398
Reaction 398
Discussion 398
Experimental Procedure 399
Experiment 33B 9-Fluorenone: NaOCl Oxidation of 9-Fluorenol 401
Reaction 401
Discussion 401
Experimental Procedure 401
EXPERIMENT 34 Hypochlorite Oxidation of Methyl Ketones by the Haloform Reaction: Benzoic Acid and p-Methoxybenzoic Acid 403
Reaction 404
Discussion 404
Experiment 34A Benzoic Acid 405
Experimental Procedure 405
Experiment 34B p-Methoxybenzoic Acid 406
Reaction 406
Experimental Procedure 406
Optional Semimicroscale Preparation 407
EXPERIMENT 35 Conversion of Cyclohexyl Bromide to Cyclohexene–An E2 Elimination Reaction: Factors Affecting the Rate of a Chemical
Reaction 409
Reaction 409
Discussion 409
Experimental Procedure 414
Data Analysis 416
Variation of Parameters 416
EXPERIMENT 36 Aqueous Suzuki Synthesis of 4-Phenylphenol 421
Reaction 421
Discussion 421
Experimental Procedure 424
Chapter 7 SEQUENTIAL SYNTHESES: THE TRANSITION FROM MACRO TO MICRO 428
SEQUENCE A The Synthesis of Hexaphenylbenzene 431
EXPERIMENTS A1a, A2a, A3a, A1b, A2b, A3b, and A4ab The Synthesis of Hexaphenylbenzene from Benzaldehyde: 434
Experiment A1a The Benzoin Condensation of Benzaldehyde: Benzoin 436
Reaction 436
Discussion 437
Semimicroscale Experimental Procedure 438
Optional Scales 439
Microscale Reaction Procedure 439
Experiment A2a Copper(II) Ion Oxidation of Benzoin: Benzil 440
Reaction 441
Discussion 441
Semimicroscale Experimental Procedure 442
Optional Microscale Preparation 444
Experiment A3a Tetraphenylcyclopentadienone 445
Reaction 445
Discussion 446
Microscale Reaction Procedure (1) 446
Microscale Reaction Procedure (2) 447
Experiment A1b (E)-Stilbene 448
Reaction 449
Discussion 449
Experimental Procedure 450
Experiment A2b Bromination of (E)-Stilbene: meso-Stilbene Dibromide 451
Reaction 452
Discussion 452
Semimicroscale Experimental Procedure 454
Experiment A3b Dehydrohalogenation of
meso-Stilbene Dibromide: Diphenylacetylene 457
Reaction 457
Discussion 457
Semimicroscale Experimental Procedure 458
Optional Macroscale and Microscale
Preparations 459
Experiment A4ab Hexaphenylbenzene 460
Reaction 461
Discussion 461
Experimental Procedure 462
SEQUENCE B The Stepwise Synthesis of Nylon-6,6 464
Experiment B1 Oxidation of Cyclohexanol: Adipic Acid 465
Reaction 465
Discussion 465
Experimental Procedure 467
Experiment B2 Preparation of an Acid Chloride: Adipoyl Chloride 468
Reaction 468
Discussion 469
Experimental Procedure 469
Experiment B3 Preparation of a Polyamide: Nylon-6,6 471
Reaction 471
Discussion 471
Experimental Procedure 472
SEQUENCE C The Synthesis of Sulfanilamide 473
The Sulfa Drugs 473
Experiment C1 Acetylation of Aniline: 2,2,2-Trifluoroacetanilide 474
Reaction 475
Discussion 475
Experimental Procedure 476
Experiment C2 Chlorosulfonation of 2,2,2-
Trifluoroacetanilide: p-(Trifluoroacetamido) benzenesulfonyl Chloride 477
Reaction 478
Discussion 478
Experimental Procedure 479
Experiment C3 Preparation of an Arene Sulfonamide: Sulfanilamide 480
Discussion 481
Experimental Procedure 481
Chapter 8 SPECTROSCOPIC IDENTIFICATION OF ORGANIC COMPOUNDS 484
Infrared Spectroscopy 484
Introduction to Group Frequencies: Interpretation of Infrared Spectra 485
A Survey of Group Frequencies Identified in Organic Molecules 488
Group Frequencies of the Hydrocarbons 489
Group Frequencies of Carbonyl
Groups: C O 490
Group Frequencies of the Heteroatom Functional Groups 492
Esters 493
Infrared Spectroscopy Instrumentation and Sample Handling 496
Instrumentation 496
Sample Handling in the Infrared 497
Nuclear Magnetic Resonance Spectroscopy 504
Nuclear spin 504
Instrumentation 505
Chemical Shift 508
Spin–Spin Coupling 509
Intensities 512
Second-Order Effects 513
Interpretation of 1H NMR Spectra 514
1H Chemical Shifts 517
Spin–Spin Coupling 518
Geminal Coupling 518
Vicinal Coupling 518
Long-Range Coupling 520
Examples of Complex, Yet First-Order, Coupling 520
Ethyl Vinyl Ether 520
Allyl Acetate 522
13C NMR Spectroscopy 525
Two-Dimensional NMR Spectroscopy 531
Nuclear Magnetic Resonance Sampling 532
Ultraviolet–Visible Spectroscopy: Introduction to Absorption Spectroscopy 537
UV–VIS Spectroscopy 539
Application to Organic Molecules 540
Instrumentation 547
The Source of Radiation 548
The Monochromator 549
Sample Compartment 550
The Detector 550
The Electronics: The Amplifier and Recorder 550
Sample Preparation 551
Criteria for Choosing a Solvent 552
Mass Spectrometry 553
Instrumentation 555
Ion Source 556
Mass Analyzer 557
Detector 559
Tuning the Mass Spectrometer 559
Sample Introduction 560
Gas Chromatography/Mass Spectrometry (GC/MS) 560
Capillary Columns 560
Split Injection 561
Split/Splitless Injection 561
Features of the Mass Spectrum 562
Terms 563
Isotope Peaks 563
Recognizing the Molecular Ion 565
Mass Spectral Interpretation 566
Case Study: Synthesis of Methyl Benzoate 567
Chapter 9 QUALITATIVE IDENTIFICATION OF ORGANIC COMPOUNDS 573
Organic Qualitative Analysis 573
Preliminary Tests 575
Nonchemical Tests 575
Ignition Test 576
Separation of Impurities 577
Detection of Elements Other Than Carbon, Hydrogen, or Oxygen 578
Sodium Fusion 578
Sulfur 579
Nitrogen 580
The Halogens (Except Fluorine) 580
Solubility Characteristics 582
The Classification Tests 584
Alcohols 584
Periodic Acid: Vicinal Diols 586
Aldehydes and Ketones 586
Alkanes and Cycloalkanes: Saturated Hydrocarbons 588
Alkenes and Alkynes: Unsaturated Hydrocarbons 589
Alkyl Halides 589
Amides, Ammonium Salts, and Nitriles 591
Amines 592
Aromatic Hydrocarbons with no Functional Groups 593
Carboxylic Acids 594
Esters 594
Ethers 595
Methyl Ketones and Methyl Carbinols 595
Nitro Compounds 596
Phenols and Enols 597
Preparation of Derivatives 598
Carboxylic Acids 599
Preparation of Acid Chlorides 599
Amides 599
Anilides 600
Toluidides 600
Alcohols 600
Phenyl- and -Naphthylurethanes (Phenyl- and -Naphthylcarbamates) 600
3,5-Dinitrobenzoates 601
Aldehydes and Ketones 602
2,4-Dinitrophenylhydrazones 602
Semicarbazones 602
Amines 602
Primary and Secondary Amines: Acetamides 602
Primary and Secondary Amines: Benzamides 603
Primary, Secondary, and Tertiary Amines: Picrates 603
Acid Chlorides and Anhydrides 604
Amides 604
Aromatic Hydrocarbons 604
Picrates 604
Nitriles 604
Hydrolysis to Amides 604
Phenols 605
-Naphthylurethanes (-Naphthylcarbamates) 605
Bromo Derivatives 605
Aliphatic Hydrocarbons, Halogenated Hydrocarbons, Amides, Nitro Compounds, Ethers, and Esters 606
Glossary 609
Index 612
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