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In this laboratory experiment, students work in pairs to synthesize a simple aliphatic polycarbonate via ring-opening polymerization of trimethylene carbonate using 1,8-diazabicyclo[5.4.0]undec-7-ene and thiourea as organocatalysts. Following polymer isolation, students cool the material in a dry ice/acetone bath to observe its glass-transition behavior. This experiment is convenient to perform under teaching laboratory conditions and reinforces key concepts learned in second-year undergraduate organic chemistry, for example, nucleophilic acyl substitution, transesterification reactions, and Lewis acidity–basicity. Additionally, the experiment introduces students to polymer chemistry, heterocycles, materials science, and green chemistry. It also covers interesting concepts that are less frequently encountered at the undergraduate level such as biomimetic chemistry, bifunctional catalysis, and polymer–glass transitions.

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

Morita-Baylis-Hillman diene adducts are used as substrates in the palladium-catalyzed asymmetric allylic alkylation reaction with oxygen and carbon nucleophiles in good regio- and enantioselectivity.

[reaction; see text] The asymmetric synthesis of the oxindole alkaloid horsfiline is described. A palladium-catalyzed asymmetric allylic alkylation (AAA) is used to set the spiro(pyrrolidine-oxindole) stereogenic center.

The oxa-Pictet-Spengler reaction of 1-(3-furyl)alkan-2-ols with aldehydes catalyzed by p-toluenesulfonic acid gives good yields of the corresponding cis-5,7-disubstituted 4,5-dihydro-7H-furano[2,3-c]pyrans.

The oxa-Pictet-Spengler reaction of 1-(3-furyl)alkan-2-ols with aldehydes catalyzed by p-toluenesulfonic acid gives good yields of the corresponding cis-5,7-disubstituted 4,5-dihydro-7H-furano[2,3-c]pyrans.

Morita−Baylis−Hillman diene adducts are used as substrates in the palladium-catalyzed asymmetric allylic alkylation reaction with oxygen and carbon nucleophiles in good regio- and enantioselectivity.