One-pot conversion of trimethylsilyl ethers into urethanes using chlorosulfonyl isocyanate: application to the synthesis of a novel neuromodulator carisbamate.
This paper reports a novel synthetic method for the preparation of various urethanes and the application to the synthesis of carisbamate. The reaction of primary (2a, 2e and 2f) or secondary (2g-2i) trimethylsilyl ethers with chlorosulfonyl isocyanate afforded the corresponding urethanes in good yields without affecting the olefin moiety. However, in the case of secondary benzylic trimethylsilyl ether 2j, the corresponding urethane 3j was obtained in low yield. From the difference in reactivity between the primary and secondary benzylic trimethylsilyl ethers, the one-pot synthesis of carisbamate 1 from bis-trimethylsilyl ether 2l was achieved.
Dong
Guang Ri
GR
College of Pharmacy, Sungkyunkwan University, Suwon 440-746, Korea.
Li
Qing Ri
QR
Woo
Seol Hee
SH
Kim
In Su
IS
Jung
Young Hoon
YH
D000475:Alkenes / Q000737:chemistry; D002219:Carbamates / Q000737:chemistry*; D007202:Indicators and Reagents; D017953:Isocyanates / Q000737:chemistry*; D014297:Trimethylsilyl Compounds / Q000737:chemistry*; D014520:Urethane / Q000031:analogs & derivatives* / Q000138:chemical synthesis*
D000475:Alkenes; D002219:Carbamates; D007202:Indicators and Reagents; D017953:Isocyanates; C518914:S-2-O-carbamoyl-1-o-chlorophenyl-ethanol; D014297:Trimethylsilyl Compounds; C487390:chlorosulfonyl isocyanate; D014520:Urethane