Rearrangements of organic peroxides and related processes

• Ivan A. Yaremenko,
• Vera A. Vil’,
• Dmitry V. Demchuk and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2016, 12, 1647–1748, doi:10.3762/bjoc.12.162

Cascade alkylarylation of substituted N-allylbenzamides for the construction of dihydroisoquinolin-1(2H)-ones and isoquinoline-1,3(2H,4H)-diones

• Ping Qian,
• Bingnan Du,
• Wei Jiao,
• Haibo Mei,
• Jianlin Han and
• Yi Pan

Beilstein J. Org. Chem. 2016, 12, 301–308, doi:10.3762/bjoc.12.32

• -methylallyl)benzamide (4a) and cyclohexane (2a) as model compounds (Table 1). As shown in Table 1, we found that the reactions did not happen or gave only a trace amount of the desired product with K2S2O8, AIBN, BPO and TBHP as oxidants (Table 1, entries 1, 3–5). PhI(OAc)2 and DCP could be used as oxidants

Recent advances in copper-catalyzed C–H bond amidation

• Jie-Ping Wan and
• Yanfeng Jing

Beilstein J. Org. Chem. 2015, 11, 2209–2222, doi:10.3762/bjoc.11.240

• ] reported the copper-catalyzed, tert-butyl hydroperoxide (TBHP)-assisted C–H amidation of tertiary amines 1. By heating at 80 °C, the C–H bond in dimethylaniline underwent direct amidation to provide products 3 in the presence of amides 2. On the other hand, the dephenylation transformation via C–C bond

• ) via the intramolecular amidation of N-methyl-o-formylbenzamide (59) (Scheme 16). More recently, Lan et al. [66] realized the C–H amidation of N,N-dialkylformamides 61 using pyridine-2-yl-functionalized amides 62 or 63. Under catalytic conditions consist of CuBr and TBHP, imides 64 and 65 were afforded

Stereoselective synthesis of hernandulcin, peroxylippidulcine A, lippidulcines A, B and C and taste evaluation

• Marco G. Rigamonti and
• Francesco G. Gatti

Beilstein J. Org. Chem. 2015, 11, 2117–2124, doi:10.3762/bjoc.11.228

• epoxidation of 5 with tert-butylhydroperoxide (TBHP) in toluene gave 6 ([α]D +34.2° (c 1.3, CHCl3)) in 95% yield [9][22]. Then, the diol 7 was obtained in 85% yield from the reduction of epoxide 6 with LiAlH4 in THF at 0 °C. The diol 7 was easily purified by crystallization (85% yield, n-hexane at −50 °C up

• conditions: (a) (i) t-BuOK, BuLi, hexane, −10 °C/rt; 2 h; (ii) BrCH2CH=C(CH3)2; −10°C/rt, 1 h; (b) TBHP, cat. VO(acac)2, toluene, rt, 13 h; (c) LiAlH4, THF, 0 °C, 5 h; (d) DMP, CH2Cl2, 0 °C/rt, 14 h; (e) TMSCl, CH2Cl2/pyridine (2:1), rt, 13 h; (f) LDA, TMSCl or TESCl, −78 °C/rt, THF; (g) see Table 2; (h

Cross-dehydrogenative coupling for the intermolecular C–O bond formation

• Igor B. Krylov,
• Vera A. Vil’ and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2015, 11, 92–146, doi:10.3762/bjoc.11.13

P(O)R₂-directed Pd-catalyzed C–H functionalization of biaryl derivatives to synthesize chiral phosphorous ligands

• Rong-Bin Hu,
• Hong-Li Wang,
• Hong-Yu Zhang,
• Heng Zhang,
• Yan-Na Ma and
• Shang-dong Yang

Beilstein J. Org. Chem. 2014, 10, 2071–2076, doi:10.3762/bjoc.10.215

• (20 mol %), AgOAc (1.5 mmol), TFE (3.0 mL), 100 °C, 24 h, air atmosphere; bSubstrate (0.3 mmol), PhI(OAc)2 (0.9 mmol), Pd(OAc)2 (10 mol %), TFE (3.0 mL), 100 °C, 24 h, air atmosphere; cSubstrate (0.3 mmol), TBHP (1.2 mmol), benzyl alcohol (0.75 mmol), Pd(TFA)2 (10 mol %), DCE (3.0 mL), 60 °C, air

An oxidative amidation and heterocyclization approach for the synthesis of β-carbolines and dihydroeudistomin Y

• Suresh Babu Meruva,
• Akula Raghunadh,
• Raghavendra Rao Kamaraju,
• U. K. Syam Kumar and
• P. K. Dubey

Beilstein J. Org. Chem. 2014, 10, 471–480, doi:10.3762/bjoc.10.45

• product 6 was confirmed by LCMS analysis of the crude reaction mixture. However under these conditions product 6 was observed in less than 5% and our attempt to isolate the eudistomin Y (6) in pure form was not successful. The oxidation of compound 7 with oxygen, KMnO4, MnO2 and TBHP as well as

Recent applications of the divinylcyclopropane–cycloheptadiene rearrangement in organic synthesis

• Sebastian Krüger and
• Tanja Gaich

Beilstein J. Org. Chem. 2014, 10, 163–193, doi:10.3762/bjoc.10.14

• with Triton B and TBHP yielded the epoxide resulting from top-face attack. The surplus Cbz-group was then deprotected using TMSI [167][168]. The final azetidine formation took place upon refluxing in ethanol to give gelsemoxonine (197). Further synthetic applications The group of Wender applied the

Recent advances in transition metal-catalyzed Csp²-monofluoro-, difluoro-, perfluoromethylation and trifluoromethylthiolation

• Grégory Landelle,
• Armen Panossian,
• Sergiy Pazenok,
• Jean-Pierre Vors and
• Frédéric R. Leroux

Beilstein J. Org. Chem. 2013, 9, 2476–2536, doi:10.3762/bjoc.9.287

• . investigated the copper-catalyzed trifluoromethylation of aryl and vinyl boronic acids with in situ generated CF3-radicals using NaSO2CF3 (Table 27 and Table 28) [97]. The CF3 radical is generated from the reaction of TBHP (t-BuOOH) with NaSO2CF3. Transmetallation of the arylboronic acid with the Cu(II

• stable and inexpensive electrophilic trifluoromethyl radical source to access trifluoromethyl-substituted alkenes [62]. Cinnamic acids were reacted with sodium trifluoromethanesulfinate and a catalytic amount of copper(II) sulfate in the presence of tert-butyl hydroperoxide (TBHP) as the radical

• the reaction. The radical CF3• is generated by the reaction of TBHP with NaSO2CF3 and the catalytic source of Cu(II). The Cu(I) reduced from the former step reacts with the cinnamic acid in the presence of TBHP to afford a cupric cinnamate, which then undergoes the addition of the trifluoromethyl

Iron-catalyzed decarboxylative alkenylation of cycloalkanes with arylvinyl carboxylic acids via a radical process

• Jincan Zhao,
• Hong Fang,
• Jianlin Han and
• Yi Pan

Beilstein J. Org. Chem. 2013, 9, 1718–1723, doi:10.3762/bjoc.9.197

• reactions. Additionally, metal-free methodologies, which use TBHP, PhI(OAc)2, TBAI, I2 or Lewis/Brønsted acids, have also been employed for cross-dehydrogenative coupling reactions [48][49][50][51][52][53][54][55][56][57]. Owing to the general low reactivity of cycloalkane C(sp3)–H bonds, the direct

• ) in the presence of iron(II) chloride tetrahydrate (20 mol %) and 2.0 equiv of di-tert-butyl peroxide (DTBP) as the oxidant at 120 °C under nitrogen, which provided the expected (E)-(2-cyclohexylvinyl)benzene (3a), but in a moderate 54% yield (Table 1, entry 1). The use of aqueous TBHP as oxidant

A reductive coupling strategy towards ripostatin A

• Kristin D. Schleicher and
• Timothy F. Jamison

Beilstein J. Org. Chem. 2013, 9, 1533–1550, doi:10.3762/bjoc.9.175

• ]. Disappointingly, treatment of 55 with IBr or I2 led to exhaustive decomposition of the material. Similarly, attempts to convert the homoallylic olefin of 55 into the epoxide via directed oxidation with VO(acac)2 and TBHP again resulted in an intractable mixture of products. While investigations into installing

Selective copper(II) acetate and potassium iodide catalyzed oxidation of aminals to dihydroquinazoline and quinazolinone alkaloids

• Matthew T. Richers,
• Chenfei Zhao and
• Daniel Seidel

Beilstein J. Org. Chem. 2013, 9, 1194–1201, doi:10.3762/bjoc.9.135

• tetrahydroquinazoline aminals are converted to quinazolinones using tert-butylhydroperoxide (TBHP) and catalytic potassium iodide [36][37]. While these examples deal with the oxidation of bicyclic aminals, we were interested in developing methods to create dihydroquinazoline and quinazolinone alkaloids from ring-fused

• aminals. Here we present catalytic methods for the synthesis of both these compound classes from aminals using Cu(OAc)2/O2/AcOH and KI/TBHP systems, respectively. Results and Discussion Copper-catalyzed oxidations of aminals to dihydroquinazolines Copper-catalyzed oxidation reactions have received a great

• the oxidation of aminals to quinazolines provided an increased yield of 50% (Table 3, entry 9). The best yields were obtained by using the conditions developed by Reddy and co-workers [36], namely the combined use of catalytic amounts of potassium iodide (20 mol %) and excess TBHP (5 equiv), followed

Recent progress on the total synthesis of acetogenins from Annonaceae

• Nianguang Li,
• Zhihao Shi,
• Yuping Tang,
• Jianwei Chen and
• Xiang Li

Beilstein J. Org. Chem. 2008, 4, No. 48, doi:10.3762/bjoc.4.48

• acetogenin isolated from Annona muricata in 1998 [41]. To establish the absolute configuration of cis-solamin, two candidates 71a and 71b were synthesized by Makabe’s group in 2002 employing a TBHP-VO(acac)2 diastereoselective epoxidation followed by a cyclization strategy (Scheme 10) [42]. In their