Synthesis, effect of substituents on the regiochemistry and equilibrium studies of tetrazolo[1,5-a]pyrimidine/2-azidopyrimidines

• Elisandra Scapin,
• Paulo R. S. Salbego,
• Caroline R. Bender,
• Alexandre R. Meyer,
• Anderson B. Pagliari,
• Tainára Orlando,
• Geórgia C. Zimmer,
• Clarissa P. Frizzo,
• Helio G. Bonacorso,
• Nilo Zanatta and
• Marcos A. P. Martins

Beilstein J. Org. Chem. 2017, 13, 2396–2407, doi:10.3762/bjoc.13.237

• , resulting in a 2-azidopyrimidine compound. The structures of compounds 7a,b and 7f were also confirmed by IR spectroscopy in the solid state. The FTIR spectrum, recorded using a KBr pellet, exhibited a strong absorption band corresponding to the azido group [47] at 2140 cm−1 and 2160 cm−1, thus

Synthesis and photophysical properties of novel benzophospholo[3,2-b]indole derivatives

• Mio Matsumura,
• Mizuki Yamada,
• Atsuya Muranaka,
• Misae Kanai,
• Naoki Kakusawa,
• Daisuke Hashizume,
• Masanobu Uchiyama and
• Shuji Yasuike

Beilstein J. Org. Chem. 2017, 13, 2304–2309, doi:10.3762/bjoc.13.226

• NMR signals of gold and boron complexes 8 and 9 were observed at δ = 6.0 and 11.5 ppm, respectively. These results show that the electronic nature of the phosphorus atoms is similar to that of the oxidized species 4–7 (δ = 6.0–27.0 ppm). In the IR spectrum of 4 in KBr, a strong absorption for P=O

Solid-state studies and antioxidant properties of the γ-cyclodextrin·fisetin inclusion compound

• Joana M. Pais,
• Maria João Barroca,
• Maria Paula M. Marques,
• Filipe A. Almeida Paz and
• Susana S. Braga

Beilstein J. Org. Chem. 2017, 13, 2138–2145, doi:10.3762/bjoc.13.212

• . Infrared spectra were obtained as KBr pellets in a Mattson 7000 FTIR spectrometer (resolution 2.0 cm−1; 64 scans per spectrum). 13C{1H} CP/MAS NMR spectra were recorded at 100.62 MHz on a (9.4 T) Bruker Avance III 400 spectrometer, with an optimized π/2 pulse for 1H of 4.5 μs, 3 ms contact time, a spinning

Enzymatic separation of epimeric 4-C-hydroxymethylated furanosugars: Synthesis of bicyclic nucleosides

• Neha Rana,
• Manish Kumar,
• Vinod Khatri,
• Jyotirmoy Maity and
• Ashok K. Prasad

Beilstein J. Org. Chem. 2017, 13, 2078–2086, doi:10.3762/bjoc.13.205

• Novozymes Inc., Copenhagen, Denmark. For all the lipase-mediated reactions, AR grade organic solvents were used, which were purchased from SD Fine-Chem Ltd., Mumbai, India. The IR spectra were recorded by using thin film for oils and by making KBr discs for solid samples. The 1H and 13C NMR spectra were

Mechanically induced oxidation of alcohols to aldehydes and ketones in ambient air: Revisiting TEMPO-assisted oxidations

• Andrea Porcheddu,
• Evelina Colacino,
• Giancarlo Cravotto,
• Francesco Delogu and
• Lidia De Luca

Beilstein J. Org. Chem. 2017, 13, 2049–2055, doi:10.3762/bjoc.13.202

• ), TEMPO (1–2 mol %), KBr (10 mol %), NaHCO3 (pH 8.6), CH2Cl2/H2O. b) Stahl protocol: [Cu(MeCN)4](OTf) (5 mol %), bpy (5 mol %), TEMPO (5 mol %), NMI (10 mol %), CH3CN, air. c) Gao (2016) protocol: Fe(NO)3.9H2O (10 mol %), 9-azabicyclo[3.3.1]nonan-N-oxyl (ABNO, 1–3 mol %), CH3CN, air. TEMPO-assisted

Mechanochemical synthesis of small organic molecules

• Tapas Kumar Achar,
• Anima Bose and
• Prasenjit Mal

Beilstein J. Org. Chem. 2017, 13, 1907–1931, doi:10.3762/bjoc.13.186

• ][133] in which the component aldehyde and catalytic amount of acid were generated in situ for the final step of dihydropyrimidinone synthesis. Benzyl alcohols were oxidized by a reagent combination of oxone (0.6 equiv), KBr (10 mol %) and 2,2,6,6-tetramethylpiperidin-1-yloxy radical (TEMPO, 1 mol %) to

A novel application of 2-silylated 1,3-dithiolanes for the synthesis of aryl/hetaryl-substituted ethenes and dibenzofulvenes

• Grzegorz Mlostoń,
• Paulina Pipiak,
• Róża Hamera-Fałdyga and
• Heinz Heimgartner

Beilstein J. Org. Chem. 2017, 13, 1900–1906, doi:10.3762/bjoc.13.185

• with a FTIR NEXUS spectrometer (as film or KBr pellets). High resolution MS measurements were performed with a GCT Premier Waters instrument. Melting points were determined in capillaries with a Stuart SMP30 apparatus with automatic temperature monitoring. Microwave-supported syntheses of thioketones 1

• were purified by column chromatography (Et2O/CH2Cl2 8:2). 1,1,2,2-Tetrakis(selenophen-2-yl)ethene (9c): Yield: 236 mg (87%); chromatographic purification (petroleum ether/CHCl3 8:2). Orange crystals; mp 199–202 °C; IR (KBr) ν: 3085 (w), 1445 (m), 1429 (m), 1236 (s), 1182 (m), 1116 (m), 1024 (m), 849 (m

• ; found: C, 39.68; H, 2.25. 1,2-Diphenyl-1,2-bis(selenophen-2-yl)ethene (9f, mixture of E/Z isomers, ratio 2:1.2). Yield: 156 mg (71%); chromatographic purification (petroleum ether/CHCl3 8:2). Yellow crystals; mp 221–223 °C; IR (KBr) ν: 3044 (w), 1483 (w), 1439 (m), 1233 (m), 1201 (w), 1071 (w), 1021 (w

The chemistry and biology of mycolactones

• Matthias Gehringer and
• Karl-Heinz Altmann

Beilstein J. Org. Chem. 2017, 13, 1596–1660, doi:10.3762/bjoc.13.159

Phosphorus pentasulfide mediated conversion of organic thiocyanates to thiols

• Chandra Kant Maurya,
• Avik Mazumder and
• Pradeep Kumar Gupta

Beilstein J. Org. Chem. 2017, 13, 1184–1188, doi:10.3762/bjoc.13.117

• (KBr, νmax): 3155, 3065, 2929, 2872, 2362, 1695, 1598, 1242 cm−1; 1H NMR (600 MHz, CDCl3) δ 7.30–7.27 (m, 2H), 6.96–6.89 (m, 3H), 4.06 (t, J = 12 Hz, 2H, OCH2), 3.42 (t, J = 12 Hz, 2H, SCH2), 2.21 (qn, J =12 Hz, 2H, CCH2), 1.28 (s, 1H, SH); 13C{1H} NMR (125 MHz, CDCl3) δ 158.66, 129.51, 120.91, 114.53

• , 65.98, 33.62, 28.77; EIMS (m/z): 51 (7), 65 (12), 66 (8), 74 (10), 75 (7), 77 (16), 94 (100), 95 (8), 168 (20); HRMS (ESI) m/z: [M + Na]+ calcd for C9H12OSNa, 191.0609; found, 191.0610. 2-(Phenylthio)ethanethiol (8) Oil (1.51 g, 89%). IR (KBr, νmax): 3059, 2964, 2363, 1261, 1094, 1026 cm−1; 1H NMR (600

• (8), 123 (28), 170 (26); HRMS (ESI) m/z: [M + Na]+ calcd for C8H10S2Na, 193.0224; found, 193.0225. 3-Chlorobenzylthiol (11) Oil (1.28 g, 81%). IR (KBr, νmax): 2965, 2363, 1262, 1096, 1026 804 cm−1; 1H NMR (600 MHz, CDCl3) δ 7.25–7.17 (m, 2H), 7.13–7.04 (m, 3H), 3.49 (s, 2H, CH2), 1.18 (s, 1H, SH

Regioselective (thio)carbamoylation of 2,7-di-tert-butylpyrene at the 1-position with iso(thio)cyanates

• Anna Wrona-Piotrowicz,
• Marzena Witalewska,
• Janusz Zakrzewski and
• Anna Makal

Beilstein J. Org. Chem. 2017, 13, 1032–1038, doi:10.3762/bjoc.13.102

• ), 5.87 (t, J = 5.4 Hz, 1H), 3.74 (m, 1H), 3.64 (m, 1H), 1.67 (s, 9H), 1.58 (s, 9H), 1.36 (t, J = 7.2 Hz, 3H); 13C NMR (150 MHz, CDCl3) δ 171.8, 149.2, 144.0, 131.3, 131.1, 130.9, 130.3, 128.7, 128.4, 128.2, 127.2, 124.4, 123.6, 122.7, 122.7, 122.4, 122.4, 37.1, 35.2, 35.1, 32.3, 31.9, 14.4; IR (KBr, cm−1

• , 130.3, 128.4, 128.0, 127.7, 127.2, 124.3, 124.2, 122.9, 122.7, 122.3, 41.0, 37.8, 35.2, 32.6, 31.9, 12.8; IR (KBr, cm−1): 3424, 3164, 2961, 1603, 1540, 1391, 1334, 1223, 881; anal. calcd. for C27H31NS: C, 80.75; H, 7.78; N, 3.49; S, 7.98; found: C, 80.70; H, 7.80; N, 3.51, S, 7.99. Ethyl (2,7-di-tert

• , 141.9, 134.9, 131.0, 130.8, 130.2, 128.4, 127.8, 127.4, 125.9, 124.4, 123.4, 122.7, 122.6, 122.5, 122.2, 63.0, 37.6, 35.2, 32.5, 31.9, 13.8; IR (KBr, cm−1): 3447, 3383, 2961, 2906, 2868, 1769, 1479, 1227, 1137, 1043, 881; anal. calcd. for C28H31NO2S: C, 75.47; H, 7.01; N, 3.14; O, 7.18; S, 7.20; found

Substitution of fluorine in M[C₆F₅BF₃] with organolithium compounds: distinctions between O- and N-nucleophiles

• Anton Yu. Shabalin,
• Nicolay Yu. Adonin and
• Vadim V. Bardin

Beilstein J. Org. Chem. 2017, 13, 703–713, doi:10.3762/bjoc.13.69

• and PhLi were prepared from lithium and MeI or PhBr, they contain the corresponding lithium halides. It follows that the precipitate consists of KI and KBr, respectively, and the actual boron-containing reactant is lithium pentafluorophenyltrifluoroborate (1-Li). Independently, Li[C6F5BF3] was

Brønsted acid-mediated cyclization–dehydrosulfonylation/reduction sequences: An easy access to pyrazinoisoquinolines and pyridopyrazines

• Ramana Sreenivasa Rao and
• Chinnasamy Ramaraj Ramanathan

Beilstein J. Org. Chem. 2017, 13, 428–440, doi:10.3762/bjoc.13.46

• 138–139 °C; IR (KBr, cm−1): 3002, 2937, 2835, 1686, 1515, 1447, 1391, 1270, 1237, 1171, 1114, 1026, 960, 852, 811, 811, 690, 668, 572, 525; 1H NMR (400 MHz, CDCl3) δ 7.79–7.78 (m, 2H), 7.66–7.62 (m, 1H), 7.59–7.55 (m, 2H), 7.67 (d, J = 7.3 Hz, 1H), 6.69–6.66 (m, 2H), 4.11 (s, 4H), 3.86 (s, 3H), 3.84

• liquid; IR (KBr, cm−1): 2950, 2853, 1734, 1683, 1594, 1514, 1453, 1348, 1268, 1156, 1028, 806, 755, 704, 631; 1H NMR (400 MHz, CDCl3) δ 7.29–7.26 (m, 1H), 7.24–7.21 (m, 2H), 7.19–7.16 (m, 2H), 6.70 (s, 2H), 6.68 (s, 1H), 3.94–3.86 (m, 2H), 3.79 (s, 3H), 3.76 (s, 3H), 3.49 (s, 2H), 3.29 (s, 4H), 2.72-2.68

• pure form. 9,10-Dimethoxy-2-(phenylsulfonyl)-2,3,6,7-tetrahydro-4H-pyrazino[2,1-a]isoquinolin-4-one (9a) 360 mg, (90% yield) colorless liquid; IR (KBr, cm−1): 2927, 2854, 1679, 1513, 1406, 1389, 1355, 1272, 1209, 1163, 1030, 992, 726, 576; 1H NMR (400 MHz, CDCl3) δ 7.82–7.79 (m, 2H), 7.59–7.55 (m, 1H

A new class of organogelators based on triphenylmethyl derivatives of primary alcohols: hydrophobic interactions alone can mediate gelation

• Wangkhem P. Singh and
• Rajkumar S. Singh

Beilstein J. Org. Chem. 2017, 13, 138–149, doi:10.3762/bjoc.13.17

• carried out the FTIR analysis of TPM-G12 in solution (CHCl3, non-self-assembled state) and xerogel (KBr, self-assembled state) and compared their differences. Since there is no structural component capable of forming relatively strong intermolecular non-covalent interactions in TPM-G12 (e.g., hydrogen

• gel (1.5% w/v) in (a) propan-1-ol (b) DMSO. FTIR spectra of gelator TPM-G12 in (a) CHCl3 and (b) xerogel in KBr. Powder X-ray diffraction patterns of xerogel of (a) TPM-G12 from propan-1-ol and (b) TPM-G5 from DMSO. Energy minimized conformational structure of (a) TPM-G12 and (b) TPM-G5 obtained using

Synthesis and evaluation of anti-oxidant and cytotoxic activities of novel 10-undecenoic acid methyl ester based lipoconjugates of phenolic acids

• Naganna Narra,
• Shiva Shanker Kaki,
• Rachapudi Badari Narayana Prasad,
• Sunil Misra,
• Koude Dhevendar,
• Venkateshwarlu Kontham and
• Padmaja V. Korlipara

Beilstein J. Org. Chem. 2017, 13, 26–32, doi:10.3762/bjoc.13.4

• (-NH-C(O)-), 141.25 (-NH-C(O)-CH=CH-),134.81–127.83, 120.52 (-NH-C(O)-CH=CH-), 51.47 (-C(O)-OCH3-), 38.49 (-CH2-NH-), 29.44 (-S-CH2-), 29.36 (-CH2-S-), 29.22 (-CH2-CH2-S-), 29.19–24.96 (-CH2-CH2-); IR (cm−1, KBr): 2853, 2853, 1720, 1654, 1599, 1527, 1441, 1365; ESIMS (m/z): 406 [M + H]+, 428 [M + Na

• -), 31.84 (-CH2-CH2-S-), 29.69–24.96 (-CH2-CH2-); IR (cm−1, KBr): 3409, 2923, 2853, 1729, 1652, 1595, 1519, 1452, 1373; ESIMS (m/z): 422 [M + H]+, 444 [M + Na]+; HRMS (m/z): [M + H]+ calcd for C26H36O4NS, 422.23596; found, 422.23491. Synthesis of methyl 11-((2-((E)-3-(3,4-dihydroxyphenyl)acrylamido)ethyl

• )-), 146.87, 144.53, 142.53 (-NH-C(O)-CH=CH-), 127.07, 121.33, 117.12 (-NH-C(O)-CH=CH-), 115.46, 114.71, 51.60 (-C(O)-OCH3-), 39.05 (-CH2-NH-), 38.88 (-S-CH2-), 38.76 (-CH2-S-), 34.16 (-CH2-CH2-S-), 29.59–24.96 (-CH2-CH2-); IR (cm−1, KBr): 3359, 2953, 2854, 1721, 1654, 1599, 1527, 1441, 1365; ESIMS (m/z): 438

Versatile synthesis of end-reactive polyrotaxanes applicable to fabrication of supramolecular biomaterials

• Atsushi Tamura,
• Asato Tonegawa,
• Yoshinori Arisaka and
• Nobuhiko Yui

Beilstein J. Org. Chem. 2016, 12, 2883–2892, doi:10.3762/bjoc.12.287

• was mixed with KBr and pellets were prepared for FTIR measurements. Synthesis of benzylazide group-terminated PRX (4a) PEG-Ph-NH2 (300 mg, 29.9 μmol) dissolved in a small aliquot of water was added to the α-CD aqueous solution (10.3 mL, 145 mg/mL), and the mixture was stirred for 24 h at room

Synthesis of spiro[isoindole-1,5’-isoxazolidin]-3(2H)-ones as potential inhibitors of the MDM2-p53 interaction

• Salvatore V. Giofrè,
• Santa Cirmi,
• Raffaella Mancuso,
• Francesco Nicolò,
• Giuseppe Lanza,
• Laura Legnani,
• Agata Campisi,
• Maria A. Chiacchio,
• Michele Navarra,
• Bartolo Gabriele and
• Roberto Romeo

Beilstein J. Org. Chem. 2016, 12, 2793–2807, doi:10.3762/bjoc.12.278

• isomeric mixture, followed by filtration. (1RS,4'RS)-2,2'-Dibenzyl-4'-(morpholine-4-carbonyl)spiro[isoindoline-1,5'-isoxazolidin]-3-one (6a): White solid; mp 197–199 °C (Yield: 71 mg, 51%); IR (KBr) νmax: 1685, 1638 cm−1; 1H NMR (500 MHz, CDCl3) δ 7.82–7.78 (m, 1H), 7.62–7.47 (m, 5H), 7.43 (d, J = 7.1 Hz

• , 484.2262. (1RS,4'SR)-2,2'-Dibenzyl-4'-(morpholine-4-carbonyl)spiro[isoindoline-1,5'-isoxazolidin]-3-one (7a): White crystals, mp 185–187 °C (Yield: 12 mg, 9%); IR (KBr) νmax: 1680, 1642 cm−1; 1H NMR (500 MHz, CDCl3) δ 7.80 (d, J = 6.7 Hz, 1H), 7.62–7.46 (m, 4H), 7.45–7.20 (m, 10H), 5.05 (d, J = 11.6 Hz, 1H

• , 53.9, 46.1, 46.0, 40.6, 31.4, 25.9, 23.8, 20.7, 13.9; HRMS–ESI (m/z): [M + H]+ calcd for C26H32N3O3, 434.2444; found, 434.2471. (1RS,4'RS)-2'-Benzyl-2-butyl-4'-(morpholine-4-carbonyl)spiro[isoindoline-1,5'-isoxazolidin]-3-one (6c): White solid, mp 122–124 °C (Yield: 54 mg, 38%); IR (KBr) νmax: 1687

Biomimetic synthesis and HPLC–ECD analysis of the isomers of dracocephins A and B

• Viktor Ilkei,
• András Spaits,
• Anita Prechl,
• Áron Szigetvári,
• Zoltán Béni,
• Miklós Dékány,
• Csaba Szántay Jr,
• Judit Müller,
• Árpád Könczöl,
• Ádám Szappanos,
• Attila Mándi,
• Sándor Antus,
• Ana Martins,
• Attila Hunyadi,
• György Tibor Balogh,
• György Kalaus (†),
• Hedvig Bölcskei,
• László Hazai and
• Tibor Kurtán

Beilstein J. Org. Chem. 2016, 12, 2523–2534, doi:10.3762/bjoc.12.247

• ) as a white solid, mp 168–170 °C; IR (KBr) νmax: 3393, 3034, 2970, 1634, 1519, 1455, 1340, 1310, 1279, 1170, 1090 cm−1; 1H NMR (799.7 MHz, CD3OD) δH 2.21–2.27 (m, 1H, Hx-4”), 2.36–2.42 (m, 1H, Hx-3”), 2.43–2.49 (m, 1H, Hy-4”), 2.59–2.64 (m, 1H, Hy-3”), 2.71–2.75 (m, 1H, Hx-3), 3.12 and 3.13 [sum 1H

• [M + H] calcd for C19H18O6N: 356.11286; found: 356.11284; ESI–MS–MS (CID = 35%) (rel. int. %): 339(100); 338(4); 311(2); 236(3); and title compounds (±)-3a–d (21 mg, 99.92% purity), also a white solid, mp 238–240 °C; IR (KBr) νmax: 3416, 3034, 2970, 1630, 1519, 1447, 1378, 1343, 1257, 1176, 1081 cm−1

A new protocol for the synthesis of 4,7,12,15-tetrachloro[2.2]paracyclophane

• Donghui Pan,
• Yanbin Wang and
• Guomin Xiao

Beilstein J. Org. Chem. 2016, 12, 2443–2449, doi:10.3762/bjoc.12.237

• from commercial suppliers. All chemicals were used as received without further purification. 1H NMR spectra were recorded in CDCl3 using an AVANCE III 400WB spectrometer. IR spectra were recorded on a Nicolet AVATAR 5700 FTIR spectrophotometer in the range of 4000–400 cm−1 using KBr pellets. Melting

• and dried in a vacuum oven at 80 °C for 24 h. 11: highly hygroscopic solid. IR (KBr) ν/cm−1: 3004, 1635, 1617, 1477, 1375, 1190, 980. 12: highly hygroscopic solid. IR (KBr) v/cm−1: 2989, 1521, 1483, 1382, 1125, 910, 805, 722. 13: highly hygroscopic solid. IR (KBr) v/cm−1: 2968, 2935, 1632, 1452, 1371

• , 1154, 725, 672. 14: highly hygroscopic solid. IR (KBr) v/cm−1: 3009, 2946, 1642, 1458, 1381, 1205, 653. 15: highly hygroscopic solid. IR (KBr) v/cm−1: 2979, 1621, 1550, 1508, 1472, 1376, 1345, 1135, 663. Typical reaction procedure for the synthesis of substituted tetrachloro[2.2]paracyclophanes In a

New furoisocoumarins and isocoumarins from the mangrove endophytic fungus Aspergillus sp. 085242

• Ze’en Xiao,
• Senhua Chen,
• Runlin Cai,
• Shao’e Lin,
• Kui Hong and
• Zhigang She

Beilstein J. Org. Chem. 2016, 12, 2077–2085, doi:10.3762/bjoc.12.196

• spectrophotometer. Infrared spectra were recorded on a Nicolet Nexus 670 spectrophotometer using KBr discs. EIMS data were measured on a DSQ EI-mass spectrometer (Thermo, Shanghai, China) and HREIMS data were carried out on a DMAT95XP high-resolution mass spectrometer. ESIMS spectra were recorded on a Finnigan LCQ

• subsequently separated by Sephadex LH-20 CC eluted with MeOH to obtain 6 (3.1 mg). Fr. 12 was chromatographed on silica gel (petroleum ether/EtOAc, v/v, 6:4) to produce 9 (5.2 mg). Asperisocoumarin A (1): pale yellow crystals; mp 189.5–192.0 °C; UV (MeOH) λmax (log ε): 240 (4.25), 357 (3.56) nm; IR (KBr) νmax

• (c 0.02, MeOH); UV (MeOH) λmax (log ε): 220 (4.83), 248 (4.25), 317 (3.56) nm; IR (KBr) νmax: 3391, 2973, 2935, 2868, 1691, 1610, 1451, 1383, 1175, 1054 cm−1; EIMS (m/z): 262; HRMS–EI (m/z): C15H18O4 calcd for 262.1200; found, 262.1201; 1H NMR (CDCl3, 400 MHz) and 13C NMR (CDCl3, 100 MHz), see Table

Thiophene-forming one-pot synthesis of three thienyl-bridged oligophenothiazines and their electronic properties

• Dominik Urselmann,
• Konstantin Deilhof,
• Bernhard Mayer and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2016, 12, 2055–2064, doi:10.3762/bjoc.12.194

• ), 128.4 (2CH), 129.6 (2Cquat), 142.5 (2Cquat), 145.5 (2Cquat), 145.8 (2Cquat); MS (MALDI) m/z: 646.3 ([M]+); UV–vis (CH2Cl2), λmax [nm] (ε): 246 (39600), 261 (39100), 318 (27000), 395 (33100); IR (KBr) [cm−1]: 3057 (w), 2951 (w), 2926 (w), 2851 (w), 1917 (w), 1597 (w), 1576 (w), 1539 (w), 1489 (w), 1458

• (Cquat); MS (MALDI) m/z: 1208.5 ([M]+); UV–vis (CH2Cl2), λmax [nm] (ε): 266 (52100), 284 (45900), 319 (32500), 404 (27700); IR (KBr) [cm−1]: 2951 (w), 2922 (w), 2853 (w), 1456 (s), 1416 (w), 1375 (w), 1364 (w), 1331 (m), 1292 (w), 1238 (m), 1192 (w), 1138 (w), 1105 (w), 1063 (w), 1040 (w), 872 (m), 797

• ), 134.37 (Cquat), 141.9 (Cquat), 143.7 (Cquat), 143.9 (Cquat), 144.0 (Cquat), 144.20 (Cquat), 144.22 (Cquat), 145.1 (Cquat); MS (MALDI) m/z: 1770.7 ([M]+); UV–vis (CH2Cl2), λmax [nm] (ε): 267 (103000), 283 (116200), 327 (61000), 379 (51900); IR (KBr) [cm−1]: 3024 (w), 2951 (w), 2922 (w), 2851 (w), 1603 (w

Experimental and theoretical investigations on the high-electron donor character of pyrido-annelated N-heterocyclic carbenes

• Michael Nonnenmacher,
• Dominik M. Buck and
• Doris Kunz

Beilstein J. Org. Chem. 2016, 12, 1884–1896, doi:10.3762/bjoc.12.178

• -complexes in literature, we determined the symmetric and asymmetric CO stretching modes of complex 2a in dichloromethane ( = 2082 and 2003 cm−1), dimethyl sulfoxide ( = 2064 and 1984 cm−1) and as a KBr pellet ( = 2073 and 1993 cm−1). This large medium dependence shows that it is mandatory to compare the

• from Wilmad were used for the NMR experiments under CO pressure. IR spectra were recorded on a Bruker Equinox 55 FTIR spectrometer as a KBr pellet or in solution. Mass spectra were recorded on a Jeol JMS-700 and the melting point was determined with a Büchi Melting Point B 540 apparatus. The elemental

• , C11b), 126.4 (C4, C8), 152.2 (d, 1JRhC = 43.6 Hz, C6), 182.5 (d, CCO, 1JRhC = 72.7 Hz, cis-CO), 185.9 (d, 1JRhC = 54.0 Hz, trans-CO); IR (KBr, cm−1) : 3105 (w), 3058 (w), 2963 (w), 2073 (s, CO), 1993 (s, CO), 1622 (w), 1355 (w), 1331 (w), 739 (m), 704 (w); (CH2Cl2, cm−1) : 2082 (m, CO), 2003 (m, CO

Synthesis of ferrocenyl-substituted 1,3-dithiolanes via [3 + 2]-cycloadditions of ferrocenyl hetaryl thioketones with thiocarbonyl S-methanides

• Grzegorz Mlostoń,
• Róża Hamera-Fałdyga,
• Anthony Linden and
• Heinz Heimgartner

Beilstein J. Org. Chem. 2016, 12, 1421–1427, doi:10.3762/bjoc.12.136

• compared with that of a hetaryl substituent. Experimental General information: All solvents were dried over appropriate drying agents and distilled before use. Melting points were determined in a capillary using a Stewart® SMP30 apparatus. The IR spectra (KBr pellets) were recorded on a Nexus FTIR

• ): Yield: 354 mg (62%). Orange crystals; mp >162 °C (decomposition); IR (KBr) ν: 3094 (m), 3030 (w), 2967 (w), 2911 (m), 1595 (w), 1577 (w), 1488 (m), 1440 (s), 1409 (m), 1391 (m), 1233 (s), 1216 (m), 1188 (m), 1105 (s), 1084 (m), 1061 (m), 1044 (m), 1030 (s), 1001 (m), 950 (m), 816 (s), 745 (s), 717 (vs

• , [M + H]+), 571 (60, [M+]); anal. calcd for C29H24FeS2Se (571.44): C, 60.95; H, 4.23; S, 11.22; found: C, 61.04; H, 4.33; S, 11.01. 5-Ferrocenyl-5-phenylspiro[1,3-dithiolane-4,9’-[9H]fluorene] (5g): Yield: 206 mg (40%). Orange crystals; mp >185 °C (decomposition); IR (KBr) ν: 3057 (m), 2918 (m), 1636

On the mechanism of imine elimination from Fischer tungsten carbene complexes

• Philipp Veit,
• Christoph Förster and
• Katja Heinze

Beilstein J. Org. Chem. 2016, 12, 1322–1333, doi:10.3762/bjoc.12.125

• state (KBr) the NH stretching vibration appears at 3335 cm−1 (Experimental section and Supporting Information File 1). The C–N–H bending vibration is observed as a single sharp relatively strong band at 1508 cm−1. These IR data reveal that the main isomer in solution as well in the solid state is the E

• versus external H3PO4 (85%) (31P: δ = 0 ppm). IR spectra were recorded with a BioRad Excalibur FTS 3100 spectrometer as KBr disks or by using KBr cells in CH2Cl2 or in CD2Cl2. Electrochemical experiments were carried out on a BioLogic SP-50 voltammetric analyzer by using a platinum working electrode, a

• ), 99.7 (C7), 97.7 (C4), 72.1 (C2), 70.7 (C3), 70.6 (C1/10), 70.2 (C1/10), 69.1 (C8), 67.8 (C9) ppm; MS (FD) m/z (int.): 721.0 (100, [M]+); IR (KBr) : 3335 (m, NH), 3107 (s, CH), 2058 (vs, CO), 1977 (vs, CO), 1899 (br, CO), 1508 (s), 1350 (m), 1238 (m), 1057 (m), 822 (m), 600 (s), 579 (m), 480 (m) cm−1

Strecker degradation of amino acids promoted by a camphor-derived sulfonamide

• M. Fernanda N. N. Carvalho,
• M. João Ferreira,
• Ana S. O. Knittel,
• Maria da Conceição Oliveira,
• João Costa Pessoa,
• Rudolf Herrmann and
• Gabriele Wagner

Beilstein J. Org. Chem. 2016, 12, 732–744, doi:10.3762/bjoc.12.73

• -7(4H)-one 2,2-dioxide) was prepared from (1S)-(+)-10-camphorsulfonic acid following the published procedure [3]. The IR spectra were obtained from KBr pellets using a JASCO FT/IR 4100 spectrometer. NMR spectra (1H, 13C, DEPT, HSQC, HMBC, NOESY) were obtained from CD3CN solutions using a Bruker

Diradical reaction mechanisms in [3 + 2]-cycloadditions of hetaryl thioketones with alkyl- or trimethylsilyl-substituted diazomethanes

• Grzegorz Mlostoń,
• Paulina Pipiak and
• Heinz Heimgartner

Beilstein J. Org. Chem. 2016, 12, 716–724, doi:10.3762/bjoc.12.71

• [29][30]. Experimental General information: Melting points were determined in capillaries using a MEL-TEMP II apparatus (Aldrich) and are uncorrected. IR spectra were recorded with a FTIR NEXUS spectrophotometer as KBr pellets or as film; absorptions (ν) in cm−1. 1H and 13C NMR spectra were measured

• crystals; mp 66–67 °C (chromatographic purification); IR (KBr) ν: 2987 (w), 2921 (w), 1596 (w), 1490 (m), 1443 (m), 773 (m), 747 (m), 705 (s), 691 (m) cm−1; 1H NMR (600 MHz, CDCl3) δ 7.60–7.58 (m, 4H, Harom), 7.31–7.29 (m, 4H, Harom), 7.23–7.21 (m, 2H, Harom), 1.62 (s, 6H, CH3) ppm; 13C NMR (150 MHz, CDCl3

• (crude product ratio 65:35). Yield: 142 mg (63%). White crystals; mp 153–154 °C (MeOH/CHCl3); IR (KBr) ν: 3062 (w), 2919 (w), 1595 (w), 1490 (m), 1443 (m), 1231 (m), 1156 (m), 854 (w), 697 (s) cm−1; 1H NMR (600 MHz, CDCl3) δ 7.59–6.68 (m, 32H, Harom), 1.86 (s, 3H, CH3-cis), 1.70 (s, 6H, CH3-trans), 1.39