4. Experimental
Safety Note: Extreme caution should be exercised when handling the strongly oxidizing compounds chlorine, chlorine
monofluoride, chlorine trifluoride, carbonyl fluoride and hypochlorites because of their very high reactivities and hazardous
properties. We recommend wearing suitable protective equipment such as leather gloves, face shields and ear protection.
Although the described perfluoroalkyl peroxides were found to be insensitive to shock and friction[29] according to the UN
Recommendations on the Transport of Dangerous Goods[30], we cannot exclude explosive reactions in mixtures of these
perfluoroalkyl peroxides with other substances.
(F3C)3COCl: The preparation of nonafluoro-tert-butyl hypochlorite is described elsewhere.[6] IR (gas): 푣̃ [cm–1] = 1346 (w,
sh), 1322 (m, sh), 1300 (s), 1287 (vs), 1269 (s), 1264 (s), 1218 (w), 1192 (w), 1103 (m), 1004 (m), 981 (m), 785 (vw), 755
(w), 733 (m), 730 (m), 549 (w), 543 (w), 539 (w), 491 (w). UV/Vis (gas): λ [nm] = 255, 330.
(C2F5)(F3C)2COCl: Freshly distilled undecafluoro-tert-pentyl alcohol (1.816 g, 6.35 mmol) was added to CsF (50 g) in a
stainless steel reactor (V =720 mL) by condensation at liquid nitrogen temperature. The reactor was rapidly warmed to
room temperature and vigorously shaken. After cooling to –196 °C again, ClF was added (4.0 bar, 54.2 ml, 8.75 mmol,
1.38 eq.). The liquid nitrogen was removed and the empty cold dewar replaced around the steel reactor. While slowly
warming to r.t. the reactor was shaken occasionally. The crude product was collected in an external cold trap and a
subsequent trap-to-trap distillation (–65 °C / –90 °C / –196 °C) led to pure undecafluoro-tert-pentyl hypochlorite at –90 °C
as a colorless solid (1.9 g, 6 mmol, 95 %), besides C2F5Cl and (F3C)2C(O) at –196 °C. 13C NMR (neat, external [D6]acetone,
21.6 °C): δ [ppm] = 119.4 (q, 1JFC = 293 Hz, C(CF3)2), 117.2 (qt,1JFC = 287 Hz, 2JFC = 34 Hz, CF3), 110.8 (tq, 1JFC = 275 Hz,
2JFC = 41 Hz, CF2), 84.0 (tsept, 2JFC = 31, 26 Hz, Cq). 19F NMR (neat, external [D6]acetone, 20.5 °C): δ [ppm] = –69.1 (tq,
6F, 4J = 12 Hz, 5JFF = 6 Hz, C(CF3)2), –81.6 (sept, 3F, 5JFF = 6 Hz, CF3), –116.9 (sept, 2F, 4JFF = 12 Hz, 5JFF = 6 Hz, CF2).
IR (gas): 푣̃ [cm–1] = 1342 (m), 1282 (vs, sh), 1270 (vs), 1252 (vs), 1228 (s), 1172 (w), 1101 (m), 1083 (m), 998 (m), 987
(m), 973 (m), 928 (w), 905 (m, sh), 895 (m, sh), 888 (m), 781 (vw), 755 (w, sh), 743 (m), 728 (ms), 630 (w), 542 (w), 530
(w). UV/Vis (gas): λ [nm] = 255, 359.
[(F3C)3CO]2: Nonafluoro-tert-butyl hypochlorite (4.0 mmol) was transferred by condensation at liquid nitrogen temperature
into a quartz vessel. The vessel was then cooled with dry ice and irradiated for 1 h. The reaction mixture was collected in
an external cold trap. Subsequent trap-to-trap distillation (–45 °C / –78 °C / –196 °C) led to pure bis(nonafluoro-tert-butyl)
peroxide at –78 °C as a colorless solid (1.6 mmol, 80 %). The NMR and IR spectra match with those previously
reported.[15,17] 13C{19F} DEPTQ NMR (neat, external [D6]acetone, r.t.): δ [ppm] = 118.8 (CF3), 84.3 (Cq). 17O NMR
(54.19 MHz, neat, external [D6]acetone, r.t.): δ [ppm] = 246 (s). 19F NMR (neat, external [D6]acetone, r.t.): δ [ppm] = –69.6
(s). IR (gas): 푣̃ [cm–1] = 1311 (s, sh), 1302 (s, sh), 1288 (vs), 1259 (s), 1226 (w), 1110 (s), 1002 (m), 982 (m), 772 (vw),
739 (m), 731 (m), 541 (w), 496 (w). Raman (solid): 푣̃ [cm–1] = 1311 (m, sh), 1294 (m), 1278 (m, sh ), 1129 (s), 1027 (s),
872 (m, sh), 865 (s), 783 (vs), 771 (w), 749 (s), 691 (vw), 569 (w), 545 (m, sh), 541 (m), 523 (w), 356 (m), 339 (m), 326
(s, sh), 319 (s), 305 (m), 296 (w), 266 (w), 260 (w, sh), 241 (s), 194 (w), 123 (s), 118 (m, sh). UV/Vis (gas): λ [nm] = 253.
[(C2F5)(F3C)2CO]2: Undecafluoro-tert-pentyl hypochlorite (4.0 mmol) was condensed into a quartz vessel. At –50 °C the
irradiation was carried out for 1 h. After collecting the crude reaction products in an external cooling trap, pure
bis(undecafluoro-tert-pentyl) peroxide was obtained by trap-to-trap distillation (–45 °C / –78 °C / –196 °C) at –78 °C as a
colorless solid (1.0 mmol, 50 %). The NMR and IR spectra match with those previously reported.[17] 13C{19F} DEPTQ
NMR (neat, external [D6]acetone, r.t.): δ [ppm] = 118.5 (C(CF3)2), 116.7 (CF3), 115.2 (CF2), 85.6 (CC3). 19F NMR (CFCl3,
r.t.): δ [ppm] = –67.0 (m, 12F, C(CF3)2), –80.1 (m, 6F, CF3), –115.6 (sept, 4F, 4J(F,F) = 12 Hz, CF2). IR (gas): 푣̃ [cm–1] =
1340 (w), 1290 (s), 1277 (s, sh), 1269 (s), 1254 (vs), 1229 (s), 1187 (w), 1177 (w, sh), 1105 (s), 1086 (m), 1077 (m, sh),
1009 (w), 986 (m), 973 (m), 898 (s), 766 (w), 743 (s), 730 (s), 697 (vw), 656 (vw), 631 (w), 542 (w), 511 (w), 447 (vw).
Raman (solid): 푣̃ [cm–1] = 1342 (m), 1289 (w), 1277 (s), 1245 (s), 1238 (w, sh), 1177 (vw), 1132 (m), 1125 (m, sh), 1082
(m), 1009 (w), 997 (w), 853 (s), 781 (vs), 766 (m), 751 (vs), 731 (vw), 686 (w), 657 (w), 632 (m), 596 (m), 566 (m, sh), 554
(m), 548 (m), 532 (mw), 449 (w), 373 (m), 352 (m), 332 (s), 323 (m, sh), 309 (m), 295 (s), 261 (w), 243 (s), 232 (m, sh),
199 (w), 117 (s). UV/Vis (gas): λ [nm] = 250.
Conflict of interest
There is no conflict of interest.
Acknowledgements
We thank the Graduate School “Fluorine as a Key Element” (RTN 1582) and the CRC 1349 “Fluorine-Specific Interactions:
Fundamentals and Function” (project number 387284271) for financial support. We also thank the HPC Service of ZEDAT,
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