Halogenated volatiles from the fungus Geniculosporium and the actinomycete Streptomyces chartreusis

• Tao Wang,
• Patrick Rabe,
• Christian A. Citron and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2013, 9, 2767–2777, doi:10.3762/bjoc.9.311

• starting material for the preparation of the oxidising agents IBX and DMP. A contamination of a bacterial agar plate with traces of 2-iodobenzoic acid was assumed as a possible, albeit unlikely explanation for the formation of 23 in the bacterial cultures. In our laboratories all analytical work is

Garner’s aldehyde as a versatile intermediate in the synthesis of enantiopure natural products

• Mikko Passiniemi and
• Ari M.P. Koskinen

Beilstein J. Org. Chem. 2013, 9, 2641–2659, doi:10.3762/bjoc.9.300

• reduction can be used. The ester can be reduced to alcohol 6 (e.g., with NaBH4/LiCl) and then oxidized to 1 with non-basic methods (e.g., IBX/DMP [30] or TEMPO/NaOCl [31] to name a few), which will not epimerize the α-center. For our synthesis of 1, we adopted a slightly modified sequence [32]. L-Serine (2

An organocatalytic route to 2-heteroarylmethylene decorated N-arylpyrroles

• Alexandre Jean,
• Jérôme Blanchet,
• Jacques Rouden,
• Jacques Maddaluno and
• Michaël De Paolis

Beilstein J. Org. Chem. 2013, 9, 1480–1486, doi:10.3762/bjoc.9.168

• bis(aryl)methylene position with CAN has been reported [29], this is the first example of bis(heteroaryl)methylene oxidation employing this reagent [30]. In order to increase the local electron deficiency of the scaffold, 9a was oxidized with 2-iodoxybenzoic acid (IBX) into ketone 10a (98%), which

• dichloromethane were used for this work. Following our procedure [13], catalyst 6 was prepared from (±)-1-benzyl-3-aminopyrrolidine [18471-40-4]. N-Arylimino ethyl glyoxylates 2a–c were prepared by a condensation of ethyl glyoxylate and arylamines in toluene (c = 1 M) with MgSO4 at room temperature. IBX (2

• -pyrrole-2-carboxylate (10a): A solution of 9a (26 mg, 0.0593 mmol) in AcOEt (0.6 mL) was treated with IBX (50 mg, 0.178 mmol, 3 equiv). The suspension was stirred at 80 °C for 4 h before being brought to rt and filtered. Evaporation of the volatile led to analytically pure 10a which can be further

Hypervalent iodine/TEMPO-mediated oxidation in flow systems: a fast and efficient protocol for alcohol oxidation

• Nida Ambreen,
• Ravi Kumar and
• Thomas Wirth

Beilstein J. Org. Chem. 2013, 9, 1437–1442, doi:10.3762/bjoc.9.162

• [4][5][6]. Hypervalent iodine compounds in general have emerged as versatile oxidizing agents with compounds such as DMP (Dess–Martin periodinane) and IBX finding regular utility as highly selective oxidizing agents [7][8][9]. The use of the nitroxyl radical TEMPO (2,2,6,6-tetramethylpiperidine-1

Synthesis of the tetracyclic core of Illicium sesquiterpenes using an organocatalyzed asymmetric Robinson annulation

• Lynnie Trzoss,
• Jing Xu,
• Michelle H. Lacoske and
• Emmanuel A. Theodorakis

Beilstein J. Org. Chem. 2013, 9, 1135–1140, doi:10.3762/bjoc.9.126

• the corresponding C-6/C-14 diol motif. Selective TBS protection of the C-14 primary alcohol followed by an IBX oxidation of the C-6 secondary alcohol yielded ketone 19 in 80% combined yield over three steps. Triflation of the C-6 ketone with McMurry’s reagent (PhNTf2) [83][84][85][86] followed by a Pd

The crystal structure of the Dess–Martin periodinane

• Albert Schröckeneder,
• Desiree Stichnoth,
• Peter Mayer and
• Dirk Trauner

Beilstein J. Org. Chem. 2012, 8, 1523–1527, doi:10.3762/bjoc.8.172

• usually prepared from 2-iodobenzoic acid (2) in a two-step procedure, which involves oxidation with Oxone (a formulation of peroxomonosulfate) [5], followed by heating of the intermediary iodine(V) species IBX (3) with acetic anhydride and catalytic amounts of p-toluenesulfonic acid [6]. Upon repeating

• decades ago [7] and that the X-ray structure of IBX (3) was also known [8]. Browsing the Cambridge Crystallographic Data Centre, however, we were surprised to find that no X-ray structure of 1 itself has been published to date. We thus set out to investigate a range of crystallization conditions to obtain

• to rotate along the acetate C–C bonds to best fit the experimental electron density. CCDC 866010. 1-Hydroxy-1,2-benziodoxol-3(1H)-one (IBX) (3): 2-iodobenzoic acid (100 g, 403 mmol) was added to a solution of Oxone (2KHSO5/KHSO4/K2SO4) (322 g, 524 mmol) in water (2 L) and stirred at 80 °C for 4 h

Directed aromatic functionalization in natural-product synthesis: Fredericamycin A, nothapodytine B, and topopyrones B and D

• Charles Dylan Turner and
• Marco A. Ciufolini

Beilstein J. Org. Chem. 2011, 7, 1475–1485, doi:10.3762/bjoc.7.171

• , desilylation of 69 (TBAF) furnished an alcohol that, contrary to the parent 69 or other TIPS-protected synthetic intermediates, exhibited no atropisomerism (single compound by 1H and 13C NMR). Oxidation (IBX) and treatment of the emerging ketone 74 with 48% aqueous HBr in AcOH under reflux afforded synthetic

Multicomponent reaction access to complex quinolines via oxidation of the Povarov adducts

• Esther Vicente-García,
• Rosario Ramón,
• Sara Preciado and
• Rodolfo Lavilla

Beilstein J. Org. Chem. 2011, 7, 980–987, doi:10.3762/bjoc.7.110

• corresponding fused quinolines, avoiding elimination by-products. After unsuccessful attempts using palladium on carbon (decomposition), CuCl (partial oxidative elimination), Fremy’s salt (unreactive) and IBX (a complex reaction leading to unknown compounds), we focused our attention on MnO2 as the oxidant of