S1
Copper-Catalyzed Asymmetric Conjugate Additions of bis(pinacolato)diboron
and Dimethylzinc to Acyl-N-Methylimidazole Michael Acceptors: A Highly
Stereoselective Unified Strategy for 1,3,5,..n (OH, Me) Motifs Synthesis.
Jimmy Lauberteaux, Christophe Crévisy, Olivier Baslé, Renata Marcia de
Figueiredo, Marc Mauduit, and Jean-Marc Campagne
1. GENERAL CONSIDERATIONS .......................................................................................................................... S2
2. GENERAL PROCEDURES ................................................................................................................................. S3
2.1 Homologation to α,β-unsaturated Weinreb amide ........................................................................................ S3
2.2 Addition of NMI to Weinreb Amide ................................................................................................................ S3
2.3 Addition of NMI to aldehydes ......................................................................................................................... S4
2.4 Allylic alcohol oxidation .................................................................................................................................. S4
2.5 Oxidation of alcohol to aldehyde .................................................................................................................... S4
2.6 Transformation of the imidazole moiety to an ester ...................................................................................... S5
2.7 ACA of B
2
Pin
2
to α,β-unsaturated 2-acyl-N-methylimidazole ketones ........................................................... S5
2.8 Reduction of ester to aldehyde ...................................................................................................................... S6
2.9 ACA of Me
2
Zn to α,β-unsaturated 2-acyl-N-methylimidazole ketones........................................................... S6
3. PREPARATION OF THE DIETHYL 2-(METHOXY(METHYL)AMINO)-2-OXOETHYLPHOSPHONATE 12 ................... S7
4. PREPARATION OF NON-COMMERCIAL ALDEHYDES ........................................................................................ S7
5. PRELIMINARY EXPERIMENTS ......................................................................................................................... S8
6. PREPARATION OF SUBSTRATES- EARLIEST STAGES....................................................................................... S10
7. PREPARATION OF SUBSTRATES- LAST STEP : IMIDAZOLE INTRODUCTION PROCEDURE ................................ S11
8. ASYMMETRIC CONJUGATE BORYLATION (ACB) ............................................................................................ S14
8.1 Preliminary studies ....................................................................................................................................... S14
8.2 Substrate scope ............................................................................................................................................ S15
9. EXPERIMENT AT LARGER SCALE ................................................................................................................... S20
10. DETERMINATION OF ABSOLUTE CONFIGURATION ....................................................................................... S21
11. ITERATION STUDY........................................................................................................................................ S22
11.1 Post-transformation of the β-boryl acyl imidazole to the β-OTBS ester (3R,5S)-11 .................................... S22
11.2 Synthesis of the α-β-unsaturated acyl imidazole (5R,7S)-13 ....................................................................... S24
11.3 Iteration OTBS-CH
3
........................................................................................................................................ S25
11.4 Iteration OTBS-OH ........................................................................................................................................ S27