Highly Stereoselective Access to Sulfur Derivatives Starting from Zinc ­Organometallics

Abstract

A number of organozinc reagents was found to react with tetramethylthiuram disulfide [(Me₂NCS₂)₂] giving dithio­carbamates with complete retention of configuration in the case of chiral compounds.

organozinc reagents - tetramethylthiuram disulfide - sulfur - chirality

References and Notes

1 Solladié G. In Comprehensive Organic Synthesis   Vol. 6:  Trost BM. Fleming I. Winterfeld E. Pergamon Press; Oxford: 1991.  p.133-170  

2a Banwell MG. Flynn B. Hochlers DCR. Chem. Commun.  1997,  2259 

2b Banwell MG. Flynn BL. Willis AC. Hamel E. Aust. J. Chem.  1999,  52:  767 

2c Flynn BL. Verdier-Pinard P. Hamel E. Org. Lett.  2001,  3:  651 

2d Bates CG. Gujadkur RK. Venkataraman D. Org. Lett.  2002,  4:  2803 

2e Kwang FY. Buchwald SL. Org. Lett.  2002,  4:  3517 

2f Savarin C. Srogl J. Liebeskind LS. Org. Lett.  2002,  4:  4309 

3 Krasovskiy A. Knochel P. Synlett  2005,  2691 

4

The price of tetramethylthiuram disulfide is 30 Euro per kg (Aldrich).

5 Krasovskiy A. Knochel P. Angew. Chem. Int. Ed.  2004,  43:  3333 

6a Langer F. Schwink L. Devasagayaraj A. Chavant P.-Y. Knochel P. J. Org. Chem.  1996,  61:  8229 

6b Hupe E. Calaza MI. Knochel P. J. Organomet. Chem.  2003,  680:  136 

6c Hupe E. Knochel P. Angew. Chem. Int. Ed.  2001,  40:  3022 

6d Hupe E. Knochel P. Chem. Eur. J.  2003,  9:  2789 

7 Knochel P. Millot N. Rodrigues AL. Tucker CE. Org. React.  2001,  58:  417 

8

This new redox reaction is actively investigated in our laboratories.

9

This lithium salt is readily prepared by treating TMTD (1) in THF with MeLi (1 equiv, -20 °C, 10 min).

10

Typical Procedure: Preparation of Myrtanyl Dimethyldithiocarbamate ( 4d).
A 25-mL Schlenk flask containing a solution of TMTD (1.00 g, 4.16 mmol) in CH₂Cl₂ (5 mL) was cooled to 0 °C, and bis(myrtanyl)zinc (510 mg, 1.5 mmol) [6] was added slowly at this temperature. The reaction mixture was stirred for 20 h at r.t. (a white precipitate of zinc dimethyldithiocarbamate formed), then was diluted with Et₂O (30 mL) and filtered. The precipitate was washed with Et₂O, the filtrate evaporated and the residue was purified by column chromatography (pentane-CH₂Cl₂), yielding myrtanyl dimethyldithiocarbamate as colorless crystals, mp 30-31 °C (70% yield, 673 mg).