1,2-Amino Alcohols and Their Heterocyclic Derivatives as Chiral Auxiliaries in Asymmetric Synthesis

2.1.8. Michael Reaction 2245 2.1.9. Others 2247 2.2. Cyclization Reactions 2248 2.2.1. Carbon Diels−Alder Reactions 2248 2.2.2. Aza-Diels−Alder Reactions 2252 2.2.3. Other Hetero-Diels−Alder Reactions 2255 2.2.4. Ionic Diels−Alder Reaction 2256 2.2.5. 1,3-Dipolar Cycloadditions 2256 2.2.6. Other Cycloaddition Reactions 2258 2.2.7. Prins-type Cyclization 2259 2.3. Friedel−Crafts Acylation and Alkylation 2259 2.4. Baylis−Hillman Reaction 2263 2.5. Radical Addition 2264 2.6. Heterocycle Synthesis 2267 2.7. Diazocarbonyl Insertion 2270 3. C−X (X ) N, O, P, Etc.) Bond Formation 2271 3.1. Aromatic Nitration and Sulfonylation 2271 3.2. Michael Reaction 2272 3.3. Glycosylation 2273 3.4. Aziridination 2275 3.5. Diazocarbonyl Insertion 2276 3.6. Ring-Opening Reactions 2277 3.7. Other C−X Bond Formations 2280 4. Oxidation and Reduction 2280 4.1. Oxidation 2280 4.2. Reduction 2281 5. Rearrangement 2283 6. Protection and Deprotection 2285 6.1. Protection 2285 6.2. Deprotection 2288 7. Polymerization 2291 8. Miscellaneous Reactions 2291 9. Lanthanide(II) Triflates in Organic Synthesis 2295 10. Conclusion 2295 11. Acknowledgment 2295 12. References 2295

Rare-earth metal triflates in organic synthesis

The first enantioselective organocatalytic Mukaiyama−Michael reaction using α,β-unsaturated aldehydes has been accomplished. The use of iminium catalysis has provided a new strategy for the enantioselective addition of 2-silyloxy furans to unsaturated aldehydes to generate a variety of butenolide systems, an important chiral synthon found among many natural isolates. The (2S,5S)-5-benzyl-2-tert-butyl-imidazolidinone amine catalyst has been found to mediate the conjugate addition of a wide variety of substituted and unsubstituted silyloxy furans to unsaturated aldehydes. A diverse range of aldehyde substrates can be accommodated in this new organocatalytic transformation. Application of this new asymmetric technology to the enantioselective total synthesis of spiculisporic acid and the corresponding 5-epi-spiculisporic acid analogue is also discussed.

The First Enantioselective Organocatalytic Mukaiyama−Michael Reaction: A Direct Method for the Synthesis of Enantioenriched γ-Butenolide Architecture

Synthesis of optically active pheromones

The four-membered oxetane ring has been increasingly exploited for its contrasting behaviors: its influence on physicochemical properties as a stable motif in medicinal chemistry and its propensity to undergo ring-opening reactions as a synthetic intermediate. These applications have driven numerous studies into the synthesis of new oxetane derivatives. This review takes an overview of the literature for the synthesis of oxetane derivatives, concentrating on advances in the last five years up to the end of 2015. These methods are clustered by strategies for preparation of the ring and further derivatization of preformed oxetane-containing building blocks. Examples of the use of oxetanes in medicinal chemistry are reported, including a collation of oxetane derivatives appearing in recent patents for medicinal chemistry applications. Finally, examples of oxetane derivatives in ring-opening and ring-expansion reactions are described.

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Oxetanes: Recent Advances in Synthesis, Reactivity, and Medicinal Chemistry

Metal salts as new catalysts for mild and efficient aminolysis of oxiranes

Lanthanide(III) trifluoromethanesulfonates as extraordinarily effective new catalysts for the aminolysis of 1,2-epoxides

Regioalternating selectivity in the metal salt catalyzed aminolysis of styrene oxide

Efficient metal salt catalyzed azidolysis of epoxides with sodium azide in acetonitrile

In order to study the effect of a remote polar functionality on the regiochemistry of the ring opening of aliphatic epoxides, the synthesis and some nucleophilic additions (methanolysis, azidolysis, and aminolysis) of suitable 2,3-epoxy-1-alkanol derivatives (epoxides trans-1a-d and cis-2) were carried out. The C-3 selectivity commonly observed when nonchelating ring opening conditions are used is lower than when the epoxides are allowed to react in the presence of metal ions (Li + , Mg 2+ , Zn 2+ ) due to the probable intervention of bidentate-chelated intermediates in the latter case, and in some instances an almost complete C-3 regionselection is obtained

Regiochemical control of the ring-opening of 1,2-epoxides by means of chelating processes .5. synthesis and reactions of some 2,3-epoxy-1-alkanol derivatives

Marco Chini

Papers

Metal salts as new catalysts for mild and efficient aminolysis of oxiranes

Lanthanide(III) trifluoromethanesulfonates as extraordinarily effective new catalysts for the aminolysis of 1,2-epoxides

Regioalternating selectivity in the metal salt catalyzed aminolysis of styrene oxide

Efficient metal salt catalyzed azidolysis of epoxides with sodium azide in acetonitrile

Regiochemical control of the ring-opening of 1,2-epoxides by means of chelating processes .5. synthesis and reactions of some 2,3-epoxy-1-alkanol derivatives