Tributyl(3,3,3-trifluoro-1-propynyl)stannane as an efficient reagent for the preparation of various trifluoromethylated heterocyclic compounds

Five‐Membered Heterocycles with Three Heteroatoms: Triazoles

“…A more recent example showed the 1,3-dipolar cycloadditions of azido ester 10 with electron-deficient alkynes 9 to give 1,4,5-trisubstituted 1,2,3-triazoles 11 under mild conditions in water (Scheme 12.4) [36]. 1,3-Dipolar cycloaddition of tributyl (3,3,3- phenyl azide gave the corresponding 1,2,3-triazole 13, which was a useful building block for further functionalization (Scheme 12.5) [37]. An interesting approach to prepare regiospecifically 4,5-disubstituted-1,2,3-triazoles is the addition of bromomagnesium acetylides 15 to aryl azides 14 to yield 1,5-disubstituted-1,2,3-triazoles 16, which could be trapped with various electrophiles to form 1,4,5-trisubstituted 1,2,3-triazoles 17 (Scheme 12.6) [38].…”

Cross‐Coupling Reactions on Azoles with Two and More Heteroatoms

“…[154,155] Scheme 74. The tributylstannyl group was then further used for Stille cross-coupling to compounds 223 with various aryl halides (Scheme 74).…”

Metalated Heterocycles in Organic Synthesis: Recent Applications

“…Finally, an example of a useful 3-stannylated thiophene is compound 187, which has been prepared from its brominated derivative by bromo-lithium exchange, and has been used in a cross-coupling reaction for the preparation of 14 C-labeled angiotensin-(1-7)-receptor agonist AVE 0991. 348 Trifluoromethylated 5-(tri-n-butylstannyl)pyrazole 189, has been obtained recently by reaction of the propynylstannane 188 with diazomethane (Scheme 56), 349 other stannylated triazoles and isoxazoles, 28 as well as a 4-fluorinated pyrazole, 350 being prepared by related dipolar cycloaddition reactions. After N-methylation of pyrazole 189 and tin-lithium exchange followed by addition to benzaldehyde, compound 190 was obtained.…”