2.2. Thioether Oxidation 2139 2.3. Miscellaneous Oxidations 2144 3. Enantioselective Reduction Processes 2145 4. Enantioselective Nucleophilic Addition Processes 2147 4.1. Alkylation Reactions 2147 4.1.1. Aldehydes as Electrophiles 2148 4.1.2. Ketones as Electrophiles 2161 4.2. Allylation Reactions 2163 4.2.1. Aldehydes as Electrophiles 2163 4.2.2. Ketones as Electrophiles 2171 4.3. Arylation/Alkenylation Reactions 2171 4.4. Alkynylation Reactions 2172 4.4.1. Aldehydes as Electrophiles 2172 4.4.2. Ketones as Electrophiles 2174 4.5. Cyanation Processes 2174 4.5.1. Aldehydes as Electrophiles 2174 4.5.2. Ketones as Electrophiles 2179 4.6. Aldol-Type Reactions 2181 4.7. Pinacol Coupling Processes 2183 4.8. Miscellaneous Additions 2184 5. Enantioselective Friedel−Crafts Processes 2185 6. Enantioselective Cycloaddition Processes 2186 6.1. Diels−Alder Reactions 2186 6.2. [3+2]-Cycloaddition Reactions 2190 6.3. Pauson−Khand Reactions 2190 6.4. Cyclopropanation Process 2190 7. Kinetic Resolution Processes 2191 8. Enantioselective Desymmetrization Reactions 2195 9. Miscellaneous Reactions 2197 10. Conclusions and Outlook 2199 11. Acknowledgments 2199 12. References 2199

In the arena of enantioselective synthesis, titanium complexes wear the laurel wreath.

Data on the use of sulfones and sulfoxides in total stereo-, regio- and enantioselective syntheses of natural compounds published over the last 15–20 years are discussed and classified into the most important types of reactions. The bibliography includes 420 references.

http://iopscience.iop.org/article/10.1070/RC1996v065n02ABEH000204/pdf

Sulfones and sulfoxides in the total synthesis of biologically active natural compounds

Peroxo Fe(III), Mn(III), and Ti(IV) porphyrin complexes were reacted with a variety of electron-rich and electron-poor organic substrates in order to compare their reactivities with those of other known metalloperoxide complexes. The peroxoiron(III) porphyrin complex was unreactive with electron-rich substrates such as tetramethylethylene, cyclohexene, triphenylphosphine, or butyllithium but was quite reactive with electron-poor substrates such as 2-cyclohexen-1-one and 2-methyl-1,4-naphthoquinone. The peroxomanganese(III) porphyrin complex was unreactive with these electron-poor olefins but did react with the strongly electron-deficient olefin tetracyanoethylene. The peroxotitanium(IV) porphyrin complex was unreactive with both electron-rich and electron-poor olefins, as well as butyllithium, but did quantitatively oxidize triphenylphosphine to triphenylphosphine oxide. These results lead to the conclusion that the peroxo Fe(III) porphyrin complex is significantly more nucleophilic than the analogous Mn(III) and Ti(IV) complexes and than several well-known nucleophilic non-porphyrin peroxometal complexes.

Metalloporphyrin Peroxo Complexes of Iron(III), Manganese(III), and Titanium(IV). Comparative Studies Demonstrating That the Iron(III) Complex Is Extremely Nucleophilic.

Synthesis and structure-activity relationships of macrocyclic FKBP ligands

Synthetic work toward the total synthesis of nitiol has culminated in the construction of two epimeric hydroxylated derivatives, the 1,22-dihydroxynitianes. Key stereodefining steps in the construction of the A-ring fragment (13) were the use of a siloxy−epoxide rearrangement reaction, a Pauson−Khand reaction, a Norrish 1 photochemical cleavage reaction, and a highly regio- and stereoselective hydrostannylation reaction of an ynoate. The stereochemistry of the synthetically challenging C-ring fragment (20) was established using an Ireland−Claisen reaction and a Grubbs ring-closing metathesis process as key steps. The 12-membered B-ring of the nitiane skeleton was constructed using a copper-promoted Stille cross-coupling and a Kishi−Hiyama−Nozaki carbonyl addition reaction. Unfortunately, the carbonyl addition reaction produced hydroxyl functionality that could not be selectively removed. Consequently, a synthesis of epimeric 1,22-dihydroxynitianes, which are compounds that are structural hybrids of two na...

A synthetic approach toward nitiol: construction of two 1,22-dihydroxynitianes.

Synthese d'une decahydro indacenone par reaction intramoleculaire de Diels Alder a partir de l'acide ethyl-2 methyl-3 pentene-4 oique. Structure cristalline d'une lactone intermediaire

Dennis H. Burns

Papers

Ikarugamycin: total synthesis of the decahydro-as-indacene portion