Asymmetric 1,3-Dipolar Cycloaddition Reactions

Introduction Cationic domino reactions Anionic domino reactions Radical domino reactions Pericyclic domino reactions Photochemically induced domino processes Transition metal catalysis Domino reactions initiated by oxidation or reduction Enzymes in domino reactions Multicomponent reactions Special techniques in domino reactions

Domino Reactions in Organic Synthesis

Asymmetric fluorination, trifluoromethylation, and perfluoroalkylation reactions.

Update 1 of: Asymmetric Fluorination, Trifluoromethylation, and Perfluoroalkylation Reactions

Stereochemical Control in Organic-Synthesis Using Silicon-Containing Compounds

Alkylation enantioselective des dianions derives des monoesters chiraux d'acides maloniques monosubstitues avec des halogenures d'alkyles

Enantioselective construction of a quaternary asymmetric carbon center: a versatile synthesis of .alpha.-alkyl .alpha.-amino acids

The treatment of α,β-unsaturated esters having a ketone function at an appropriate position with either TBDMSOTf in the presence of Et 3 N or TMSI in the presence of (TMS) 2 NH provided, via a tandem intramolecular Michael-aldol reaction sequence, several different types of cyclobutane derivatives. The two reaction conditions were complementary. Tricyclo[4.2.1.03-8]nonanes 34 and 35, tricyclo[5.1.1.0 3,8 ]nonane 40, tricyclo[5.4.0.0 3,7 ]undecane 51, tetracyclo[5.4.0.0 3,7 .0 9,11 ]undecane 45, and the bicyclo[3.2.0]heptanes 36, 57, and 38, which have structures either partially or completely similar to those of endiandric acids A (1a), B (1b), and C (2), trihydroxydecipiadiene (3), lintenone (4), italicene (3), and filifolone (6), were stereoselectively synthesized by the tandem reaction

Synthesis of polycyclic cyclobutane derivatives by tandem intramolecular Michael-aldol reaction under two complementary conditions: TBDMSOTf-Et3N and TMSI-(TMS)2NH

Novel construction of polycyclic systems fused to cyclobutane by tandem intramolecular Michael-Aldol reaction

The radical cyclizations of (±)-(E)-3-((2-(bromomethyl)butoxy)carbonyl)- prop-2-enoates (11) and (12) and (±)-ethyl (E)-3-{N-[2-(bromomethyl)- butyl]-N-[2-(3-indolyl)ethyl]carbamoyl}prop-2-enoate (25) were carried out with (TMS) 3 SiH or Bu 3 SnH in the presence of AIBN. (-)-(2S)-2- ((tert-Butyldimethylsilyloxy)methyl)butan-1-ol (6), which was prepared by two different methods, was converted into (+)-25. The radical cycli- zation of(+)-25 produced piperidinone (18) as a diastereomeric mixture, which was transformed into tacamonine (1)

Asymmetric total synthesis of tacamonine (pseudovincamone I) via radical cyclization

Both enantiomers of the menthyl half-esters (10) and (23) of ethylmalonic acid were converted into(+)-(4S,5R)-4-(2-benzyloxyethyl)-5-ethyl-3,4,5,6-tetrahydro-2-pyrone (18). A mixture of the trans-(18) and cis-lactones (19) in a ratio of ca. 4 : 1 was prepared by way of radical cyclisation of the (E)-α,β-unsaturated esters (16), while the former (18) was synthesised with high stereoselection by the cyclisation of the (Z)-esters (26). The lactone (18) was enantioselectively transformed into (–)-protoemetimol (5) and (–)-protoemetine (4), correlated to (–)-emetine (1) and (–)-tubulosine (3).

Nobuaki Taniguchi

Papers

Enantioselective construction of a quaternary asymmetric carbon center: a versatile synthesis of .alpha.-alkyl .alpha.-amino acids

Synthesis of polycyclic cyclobutane derivatives by tandem intramolecular Michael-aldol reaction under two complementary conditions: TBDMSOTf-Et3N and TMSI-(TMS)2NH

Novel construction of polycyclic systems fused to cyclobutane by tandem intramolecular Michael-Aldol reaction

Asymmetric total synthesis of tacamonine (pseudovincamone I) via radical cyclization

Asymmetric total synthesis of(–)-protoemetinol,(–)-protoemetine,(–)-emetine, and (–)-tubulosine by highly stereocontrolled radical cyclisations