Carbon tetrabromide → HCID 14571173, compound

This known compound was prepared by a modification of the procedure in Piers, E.; Gavai, A. V. J. Org. Chem. 1990, 55, 2374. To a flame dried flask was added dry CH2Cl2 (150 mL) and triphenylphosphine (16 g, 61.2 mmol) The temperature was lowered to 0° C. and CBr4 (10.15 g, 30.6 mmol) was added portionwise. After 30 min, a solution of 3-trimethylsilylpropanal (2.0 g, 15.3 mmol) in dry CH2Cl2 (20 ml) was added. After 1 h at 0° C., the reaction was diluted with ether and filtered through celite. The celite was rinsed with ether (4×50 mL) and the combined ether solution was extracted with H2O (100 mL), saturated NaHCO3 (100 mL), saturated NH4Cl (100 mL) and brine (100 mL). The organic layer was dried (MgSO4), filtered and evaporated to give a crude white solid. The solid residue was washed with pentane. The pentane solution was concentrated and the oily residue was chromatographed on silica gel (pentane 100%) to give (4,4-dibromo-but-3-enyl)trimethylsilane as a clear oil weighing 3.7 g. 1H NMR showed 27% contamination by remaining pentane which gives a corrected yield of 62%: IR (neat, cm−1) 2953, 2922, 2898, 1620, 1443, 1413, 1249, 1176, 1034, 986, 859, 837; 1H NMR (300 MHz, CDCl3) δ0.03 (s, 9 H), 0.62-0.67 (m, 2 H), 2.06-2.14 (m, 2 H), 6.41 (t, J=7 Hz 1 H); 13C NMR (75 MHz, CDCl3) δ−1.9, 15.1, 27.7, 87.5, 141.2.

1. customThis known compound was prepared by a modification of the procedure in Piers, E
2. customTo a flame dried flask
3. customwas lowered to 0° C.
4. waitAfter 1 h at 0° C.
5. filtrationfiltered through celite
6. washThe celite was rinsed with ether (4×50 mL)
7. extractionthe combined ether solution was extracted with H2O (100 mL), saturated NaHCO3 (100 mL), saturated NH4Cl (100 mL) and brine (100 mL)
8. dry with materialThe organic layer was dried (MgSO4)
9. filtrationfiltered
10. customevaporated
11. customto give a crude white solid
12. washThe solid residue was washed with pentane
13. concentrationThe pentane solution was concentrated
14. customthe oily residue was chromatographed on silica gel (pentane 100%)

ORD record

ord-f79d7eac11534d44bf02d5f1205251a1

Source dataset

uspto-grants-2004_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06743917B2