Chemical Photocatalysis

Chemical Photocatalysis......Page 4
List of contributing authors......Page 6
Contents......Page 10
1 Burkhard König & Thorsten Bach: Introduction......Page 16
2 Peter Schroll: Early pioneers of organic photochemistry......Page 18
2.1 References......Page 30
3 Bernhard Dick: Photophysics of Photocatalysts......Page 34
3.1 Setting the Frame......Page 36
3.2 The Experimentalist’s Perspective......Page 39
3.3 The Theoreticians’ Perspective: A Closer Look......Page 46
3.3.1 Transition probabilities......Page 47
3.3.2 Orbitals......Page 51
3.4 References......Page 58
4.1 Introduction......Page 60
4.1.1 General properties......Page 61
4.2 Early examples of flavin photocatalysis......Page 63
4.3 Flavin photocatalysis in synthesis application......Page 66
4.4 Flavin-related compounds in photocatalysis......Page 73
4.5 Photooxidations via singlet oxygen mechanism......Page 74
4.7 References......Page 76
5.1 Introduction......Page 82
5.3 Enantioselective Norrish–Yang cyclization reaction of prochiral imidazolidinones......Page 84
5.4 Enantioselective photochemical [4+4]-cycloadditions and electrocyclic [4π]-ring closure of 2-pyridones......Page 86
5.5 Enantioselective [6π]-photocyclization of acrylanilides......Page 87
5.6 Enantioselective Diels–Alder reaction of a photochemically generated ortho-quinodimethane......Page 88
5.8 Intramolecular [2+2]-photocycloadditions of substituted 5,6-dihydro-1H-pyridin-2-ones......Page 89
5.9.1 Reductive radical cyclization reactions of 3-(ω-iodoalkylidene)-piperidin-2-ones......Page 90
5.9.2 Reductive radical cyclization of 3-(3-iodopropoxy)propenoic acid derivatives......Page 91
5.10 [2+2]-Photocycloaddition reactions of substituted isoquinolones......Page 92
5.11.2 Intramolecular [2+2]-photocycloadditions of 4-(2′-aminoethyl)quinolones......Page 94
5.11.3 Intramolecular [2+2]-photocycloadditions of 4-(ω-alkenyloxy)-quinol-2-ones......Page 96
5.12 Light-induced enantioselective catalysis......Page 97
5.12.2 Catalyzed enantioselective [2+2]-photocycloadditions of 4-substituted quinolones......Page 99
5.14 References......Page 101
6.2 DNA-assisted enantioselective reactions......Page 106
6.2.1 Photocatalytically active DNA (PhotoDNAzymes)......Page 108
6.2.2 Benzophenone as photosensitizer in DNA for the development of PhotoDNAzymes......Page 109
6.3 Small peptides as organocatalysts......Page 113
6.3.1 Development of peptides for photocatalytic addition to olefins......Page 116
6.5 References......Page 122
7.2 [Ru(bpy)3]²+ and its photoredox properties......Page 126
7.3 Application of [Ru(bpy)3]²+ as catalyst in the twentiethcentury......Page 128
7.4 Conclusion......Page 144
7.6 References......Page 146
8.2 Copper in visible light catalysis......Page 154
8.3 Rhenium and platinum in visible light catalysis......Page 158
8.4.2 Photocatalytic oxidative decarboxylation......Page 160
8.4.3 Oxidative degradation......Page 161
8.4.4 Isomerization......Page 163
8.6 References......Page 164
9.1 Introduction......Page 166
9.2 Stabilized iminium ions......Page 168
9.2.1 Secondary amine-catalyzed Mannich reactions......Page 169
9.2.2 Coinage metal-catalyzed alkynylation reactions......Page 171
9.2.3 NHC-catalyzed acylations......Page 173
9.3.1 Secondary amine-catalyzed α-alkylation of aldehydes......Page 174
9.3.2 Palladium-catalyzed C-H arylation......Page 178
9.3.3 Copper-catalyzed trifluoromethylation of aryl boronic acids......Page 180
9.5 References......Page 182
10.1 Introduction......Page 184
10.2 Aza-Henry Reaction......Page 188
10.3 Addition of malonates......Page 191
10.4 Mannich reaction......Page 192
10.6 Cyanation of tertiary amines......Page 193
10.7 Alkynylation......Page 194
10.10 C-heteroatom (C–P, C–O, C–N) bond formation......Page 195
10.11 Conclusion......Page 197
10.12 References......Page 198
11 Sven Rau, Michael G. Pfeffer & Robert Staehle: Metal complexes for photohydrogenation and hydrogen evolution......Page 200
11.1.1 Chromophore......Page 202
11.1.4 Reduction catalysts......Page 203
11.1.5 Intramolecular hydrogen evolving photocatalysts......Page 204
11.1.6 Oxidation catalysts......Page 205
11.1.7 Intramolecular oxidation catalysts......Page 206
11.1.8 Comparison of inter- and intramolecular photocatalysis......Page 207
11.2 Intramolecular photocatalysts for hydrogen production and hydrogenation......Page 208
11.2.1 Hydrogen production......Page 209
11.2.2 Photohydrogenation......Page 211
11.2.3 Photophysics......Page 212
11.2.4 Ru(tpphz)Pd-type catalysts as photochemical molecular devices (PMD)......Page 217
11.3 Conclusion......Page 219
11.4 References......Page 220
12.1.1.1 Band structure and band gap......Page 226
12.1.1.2 The Fermi level and charge separation......Page 229
12.1.2.1 Doping and Co-Catalysts......Page 232
12.1.2.2 Particle size effect......Page 235
12.1.3.1 TiO2 – an UV active photocatalyst......Page 236
12.1.3.2 Selected examples of visible light active photocatalysts......Page 238
12.2 Organic semiconductors......Page 245
12.2.1.2 Photoinduced electron transfer – Exciton generation and dissociation......Page 246
12.2.2.1 Linear conjugated polymers......Page 247
12.2.2.2 Conjugated polymers with layered structure......Page 250
12.3 References......Page 254
13.1.1 Polyoxometalates – Molecular metal oxide clusters......Page 262
13.1.2 Concepts in polyoxometalate photochemistry......Page 263
13.1.3 The basics of POM photochemistry......Page 264
13.2.1 Water oxidation by Ru- and Co-polyoxometalates......Page 265
13.2.2 Polyoxoniobate water oxidation......Page 266
13.2.3 Water oxidation by Dawson anions in ionic liquids......Page 267
13.2.4 Photoreductive CO2-activation......Page 268
13.3.1 Structurally adaptive systems......Page 269
13.3.2 Optimized photoactivity by metal substitution......Page 270
13.3.3 Inspiration from the solid-state world......Page 272
13.6 References......Page 273
14.1 Introduction......Page 278
14.2 The concept of potential energy surfaces......Page 279
14.3.1 QM-Methods......Page 283
14.3.1.1 Time-dependent coupled cluster response......Page 284
14.3.1.2 Time-dependent density functional theory......Page 285
14.3.2 Solvent description via the QM/MM approach......Page 286
14.3.2.1 MM methods......Page 287
14.3.2.2 QM/MM coupling......Page 288
14.4 Procedure......Page 289
14.5 Examples......Page 291
14.5.1 Roseoflavin......Page 292
14.5.2 Benzophenone in dinucleotides......Page 297
14.6 Conclusion......Page 302
14.7 References......Page 303
15.1 Introduction......Page 310
15.2 Experimental Setup......Page 313
15.3 Data Analysis......Page 315
15.3.1 SVD and rank analysis......Page 316
15.3.2 Global lifetime analysis......Page 317
15.3.4 Maximum entropy analysis......Page 318
15.4.1 RFTA alone......Page 322
15.4.2 Photooxidation of MBA with RFTA......Page 326
15.5 Discussion......Page 330
15.6 Conclusion......Page 331
15.8 References......Page 332
16.1 UV/Vis absorption spectroscopy: More than just ε!......Page 334
16.2.1 Transient absorption spectroscopy: Signals, time scales, and data processing......Page 338
16.2.2 Spectroscopy on the fs to ps time scale......Page 341
16.2.3 Spectroscopy on the ns to μs time scale......Page 345
16.2.4 Rate models and the determination of the species associated spectra of the intermediate states......Page 351
16.3.1 Diffusion limited excited state quenching with time dependent reaction rate......Page 361
16.3.2 Application of the diffusion fit function to experimental data......Page 366
16.4.1 Requirements for an accurate definition of the quantum yield......Page 372
16.4.2 Determination of the quantity of excited molecules in transient absorption measurements......Page 377
16.4.3 Example of the spectroscopic determination of reaction quantum yields: Flavin photocatalysis......Page 379
16.5.1 Sensitization by excitation energy transfer......Page 384
16.5.2 Photoredox catalysis: Requirements on catalyst and substrate......Page 385
16.6 Epilogue......Page 389
16.7 References......Page 391
Index......Page 394