Rearrangement of dimethyl(furylmethyl)ammonium and dimethyl(thienylmethyl)ammonium N-methylides. Isolation and reaction of nonaromatic intermediates
作者:Takeshi Usami、Naohiro Shirai、Yoshiro Sato
DOI:10.1021/jo00046a025
日期:1992.9
3-[(Dimethylamino)methyl]-2-methylene-2,3-dihydrofuran (5o) and 2-[(dimethylamino)methyl]-3-methylene-2,3-dihydrofuran (12o) and their thiophene analogues 5s and 12s were prepared in high yields by fluoride-ion induced desilylation of NN-dimethyl-N-[(trimethylsilyl)methyl](2-furylmethyl)ammonium (3o) and -(3-furylmethyl)ammonium iodides (10o) and their thienylmethyl analogues 3s and 10s. Compound 59 or 12s was successfully converted to 3-[(dimethylamino)methyl](2-thienylmethyl)lithium (23s) or 2-[(dimethyl-amino)methyl](3-thienylmethyl)lithium (26s), which reacted with aldehydes to give [(dimethylamino)-methyl)(2-hydroxyalkyl)thiophenes 259 or 27s, respectively.