Synthesis of isocyanides through dehydration of formamides using XtalFluor-E

A Practical and General Base‐Catalyzed Carbonylation of Amines for the Synthesis of N‐Formamides

“…2, 135.5, 135.2, 128.3, 128.1, 127.9, 127.5, 127.1, 127.0, 49.5, 43.9 2, 47.0, 41.6, 31.1, 31.0, 28.2, 26.8, 26.2, 25.7, 22.1, 22.1, 13.6, 13.5 4,159.2,124.7,124.2,124.2,124.1,124.1,122.7,122.5,115.3 (dd,21.5 Hz),47.0,46.9,40.7,40.7,33.9,29.0;19 FNMR (282 MHz,CDCl 3 138.29, 129.64, 129.25, 126.86, 126.09, 124.99, 124.24, 124.23, 44.94, 40.08, 15.04, 13. 3, 161.7, 161.7, 161.3, 161.2, 59.0, 57.2, 53.8, 53.7, 52.5, 45.3, 39.8, 35 5 (minor), 161.7 (major), 138.6, 132.0, 129.7, 129.6, 129.4, 128.9, 128.8, 44.4 (minor), 40.7 ppm (major). (d,J = 11.9 Hz,0.14 H),5H), 6.46-6.00 (m, 1H), 3.56 (q, J = 6.6, 1.68 H), 3.47 (q, J = 6.7 Hz, 0.31 H), 2.86 ppm (t, J = 7.1 Hz, 2H); 13 CNMR (75 MHz, CDCl 3 ): d = 164. 5 (minor), 161.2 (major), 138.4, 137.5, 128.7, 128.6, 128.6, 128.5, 128.5, 128.4, 128.4, 126.7, 126.4, 43.0, 39.1, 37.5, 35.3, 35 3, 161.6, 53.8, 49.2, 39.7, 39.4, 36.5, 36.4, 33.2, 33.1, 27.8, 27.7 5 (major), 142.6, 128.6, 128.4, 127.4, 127.1, 125.9, 125.6, 124.7, 51.6, 47.3, 23.3, 21. 48.0, 43.5, 42.6, 29.3, 28.8, 28.7, 28.2, 26.1, 26.1, 26.0, 25.9, 25.9, 25.8, 25.8, 19.1, 17.6 7, 38.1, 31.7, 29.4, 29.1, 29.1, 26.7, 22.5, 14. (1) [M] + ,1 42 (5), 128 (7), 100 (23), 72 (21), 58 (82), 41 (84) 139.4, 131.3, 123.5, 123.3, 119.9, 119.3, 119.2, 39.1, 35.7, 31.6, 26.1, 26.0, 25.9, 25.3, 25.3, 25.3, 23.0, 17.3, 15. 2, 161.2, 156.1, 148.4, 136.4, 121.9, 121.4, 46.7, 42.7…”

Synthesis of Nitriles from Aldoximes and Primary Amides Using XtalFluor-E

“…The initial tests were performed using aldoxime 1, derived from hydrocinnamaldehyde, using the conditions developed for the synthesis of isocyanides (Scheme 2). 9 Gratifyingly, performing the reaction at room temperature instead of -40 °C provided within one hour reaction time, the…”

“…7 We have recently reported the use of diethylaminodifluorosulfinium tetrafluoroborate ([Et 2 NSF 2 ]BF 4 , XtalFluor-E), 8 a crystalline solid initially developed as a deoxofluorinating agent with enhanced thermal stability, for the synthesis of various isocyanides through the dehydration of formamides. 9 We envisioned that if primary amides or aldoximes were used as the starting substrate instead, upon activation with XtalFluor-E and in the presence of a base, nitriles would be obtained (Scheme 1). Herein, we report this transformation.…”

XtalFluor‐E Enabled Regioselective Synthesis of Di‐Indole Sulfides by C3−H Sulfenylation of Indoles

“…Aminodifluorosulfinium salts ([R 2 NSF 2 ] + ) are attractive members of this family as they are easier handled than earlier discovered S(IV) fluorination reagents, e. g. SF 4 and diethylaminosulfur trifluoride (DAST) [2] . Indeed, the aminodifluorosulfinium salts, XtalFluor‐E and XtalFluor‐M (Figure 1), are commercially available salts whose improved thermal and chemical stability (relative to DAST) enable facile handling and storage, leading to increasingly widespread application [2–6] . XtalFluor salts are predominantly applied in combination with exogenous fluoride sources in the deoxyfluorination of alcohols and carbonyls, [2] but they have also been used in formylation, [3] ring expansion, [4] dehydration, [5] and cyclo‐dehydration reactions, [6] amongst others [7] .…”