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Over the past 20 years, the asymmetric synthesis of acyclic tetrasubstituted stereocenters by Pd-catalyzed asymmetric allylic alkylation (Pd-AAA) strategies has seen considerable growth. Despite the inherent difficulty in accessing acyclic tetrasubstituted stereocenters, creative approaches toward this problem have resulted in high stereoinduction on both electrophilic and nucleophilic reaction partners. Much of this chemistry has paved the way for unique solutions in Mo-, Ir-, and Rh-AAA, with many complimentary methods arising due to the unique regiochemical outcomes of AAA outside of Pd catalysis.1 Introduction2 Stereocontrol on Prochiral Electrophiles3 Stereocontrol on Prochiral Nucleophiles4 Temporary Cyclic Pronucleophiles5 Allylic Alkylation with Other Metals6 Conclusions and Outlook

This review highlights the advances in the literature up to May2009 in the synthesis of spirocyclic indoline natural products. Thefocus is on formation of the spirocyclic chiral center, including bothenantioselective and diastereoselective methods. This review issplit into two main sections, the first consisting of the formation ofspirooxindoles and their application towards oxindole alkaloids, andthe second covering asymmetric synthesis of spiroindoline naturalproducts. 1 Introduction 2 Spirooxindole Alkaloids 2.1 Oxidative Rearrangements 2.2 Azomethine Ylide Cycloaddition 2.3 Asymmetric Addition-Elimination 2.4 Palladium-Catalyzed Heck Reactions 2.5 Palladium-Catalyzed Allylic Alkylation 2.6 Ring Expansion 2.7 Mannich Reaction 3 Spiroindoline Alkaloids 3.1 Palladium Catalyzed Asymmetric Allylic Alkylation 3.2 [4+2] Cycloaddition 3.3 Oxidative Rearrangement 3.4 Diastereoselective Pummerer Rearrangement 3.5 Tandem Iminium Cascade 3.6 Fischer Indole Synthesis 3.6.1 Diastereoselective Ring-Closing Metathesis 3.6.2 Diastereoselective Alkylation of Chiral Lactams 3.6.3 Regioselective Schmidt Reaction 3.6.4 Diastereoselective Ketene Lactonization 3.6.5 Harley-Mason Reaction 3.6.6 S N 2-Type Indole Alkylation 3.6.7 Aza-Cope-Mannich Rearrangement 4 Conclusion

Catalytic enantioselective construction of all-carbon quaternary stereocenters, i.e. carbon atoms bearing four different carbon substituents, poses a particular challenge in organic synthesis. This review gives a comprehensive account on the currently available methods of the above transformation that afford high enantioselectivities and synthetically useful yields.

The development of a new chiral aluminum catalyst is reported. This catalyst has been applied efficiently to the asymmetric cyanosilylation of aldehydes.

This review covers the synthesis of isolabile vinylmetalloids through hydroboration, hydrosilylation, and hydrostannation, with special focus on recent developments, metal-catalyzed reactions, and synthetically useful methods.

The synthetic scope of a transition metal catalyzed enzyme metathesis as a synthesis of 1-alkenylcycloalkenes is tested. Contrary to normal expectations based upon the important sensitivity of transition metal catalyzed reactions to steric effects, severe steric congestion enhances the effectiveness of the reaction. While palladium based catalysts are generally preferred, a platinum catalyst also effects these novel cyclorearrangements

Examination of a series of ligands for a Pd-catalyzed asymmetric allylic alkylation (AAA) suggests the importance of buttressing effects for creating chiral space for high enantioselectivity.

In contrast to N-tosylsulfoximines, the relatively obscure N-nitrosulfoximines show good diastereoselectivity in alkylations and extraordinarily good leaving group properties in cyclizations via SN2 displacement. Thus, methyl phenyl N-nitrosulfoximine serves as a chiral lynchpin for construction of chiral ring systems.

A simple synthesis of (Z)-2-trimethylsilylmethyl-2-buten-1-ol from 2-butyn-1-ol provides ready access to disubstituted bifunctional conjunctive reagents such as the title compound. Palladium(0) catalysts initiate cycloaddition to electron-deficient olefins to form methylenecyclopentanes with excellent regioselectivity

Hydroxylative Knoevenagel condensation of aldehydes followed by reduction provides a simple entry to 1,4-enediols. Subjecting the dicarbonate to a palladium(0) catalyst in the presence of triisopropyl phosphite achieves a mild vinylogous deoxygenation to (E)-1,3-dienes. Stereocontrolled synthesis of the sex pheromone of the red bollworm moth, (E)-9,11-dodecadienyl acetate, and a formal synthesis of the cotton boll weevil antifeedant, α-eleostearic acid, demonstrate the utility of this new methodology