Skeletal rearrangement of 6,8-dioxabicyclo[3.2.1]octan-4-ols promoted by thionyl chloride or Appel conditions

• Martyn Jevric,
• Julian Klepp,
• Johannes Puschnig,
• Oscar Lamb,
• Christopher J. Sumby and
• Ben W. Greatrex

Beilstein J. Org. Chem. 2024, 20, 823–829, doi:10.3762/bjoc.20.74

• the alkoxytriphenylphosphonium intermediate. Several reactions of the products were investigated to show the utility of the rearrangement. Keywords: bicyclic ring; cyrene; levoglucosenone; rearrangement; thionyl chloride; Introduction The 6,8-dioxabicyclo[3.2.1]octane derivative levoglucosenone (1

• cyrene (2) allows for its use as a chiral solvent [4]. This product is emerging as a promising platform chemical for the construction of chiral small molecules for pharmaceuticals [5][6][7][8], as a building block for catalysts and auxiliaries [9][10][11], and in materials applications [12][13][14]. New

• biological ribosides. This prompted an investigation of the scope of the SOCl2-mediated rearrangement, with the aim of producing useful chiral materials for synthesis. Results and Discussion The set of bicyclic systems 10a–f with a C4 alcohol were prepared starting with cyrene (2) by alkylation and then

Oxa-Michael-initiated cascade reactions of levoglucosenone

• Julian Klepp,
• Thomas Bousfield,
• Hugh Cummins,
• Sarah V. A.-M. Legendre,
• Jason E. Camp and
• Ben W. Greatrex

Beilstein J. Org. Chem. 2022, 18, 1457–1462, doi:10.3762/bjoc.18.151

• tetraketones 11 promoted by base (Scheme 2) [25]. The equivalent reaction has not been reported for dihydrolevoglucosenone (Cyrene™) 12, and it was thought that the chiral 1,5-diketone products could be used to construct catalysts or ligands. The aldol/Michael cascade using conditions for the aldol reaction

A comprehensive review of flow chemistry techniques tailored to the flavours and fragrances industries

• Guido Gambacorta,
• James S. Sharley and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2021, 17, 1181–1312, doi:10.3762/bjoc.17.90

Suzuki–Miyaura cross coupling is not an informative reaction to demonstrate the performance of new solvents

• James Sherwood

Beilstein J. Org. Chem. 2020, 16, 1001–1005, doi:10.3762/bjoc.16.89

• conventional solvents. In this work, the suitability of the Suzuki–Miyaura reaction to demonstrate the usefulness of new solvents was evaluated, including Cyrene™, dimethyl isosorbide, ethyl lactate, 2-methyltetrahydrofuran (2-MeTHF), propylene carbonate, and γ-valerolactone (GVL). It was found that the cross

• ) and 0.6 mmol (1 equivalent) of an aryl bromide. The solvent screening included twelve solvents. The following eminent green and bio-based solvents were included in the study to assess their ability to substitute conventional solvents: Cyrene™ [3], and its alcohol equivalent levoglucosanol [9], ethyl

• (Scheme 1a). In this work the proportion of water added is less than that previously optimised for reactions in Cyrene™ [3], and more than that previously optimised for reactions in DMI [6]. In case study 1, the majority of solvents resulted in conversion to the product in the range of 75–85% after 1 hour

An improved synthesis of adefovir and related analogues

• David J. Jones,
• Eileen M. O’Leary and
• Timothy P. O’Sullivan

Beilstein J. Org. Chem. 2019, 15, 801–810, doi:10.3762/bjoc.15.77

• starting material and the formation of only trace amounts of product. No reaction was observed in cyrene (Table 2, entry 18), often employed as a green alternative to DMF [55]. In a bid to replace DMF as the solvent, we turned our attention to more soluble adenine analogues and investigated the formation

Scope and limitations of a DMF bio-alternative within Sonogashira cross-coupling and Cacchi-type annulation

• Kirsty L. Wilson,
• Alan R. Kennedy,
• Jane Murray,
• Ben Greatrex,
• Craig Jamieson and
• Allan J. B. Watson

Beilstein J. Org. Chem. 2016, 12, 2005–2011, doi:10.3762/bjoc.12.187

• -commercial/expensive catalysts, and yield [25][26][27][28][29][30]. Consequently, poor choice of solvent replacement can result in one of industry’s workhorse reactions becoming rather less predictable and robust. In this regard, dihydrolevoglucosenone (Cyrene, Figure 1), accessed in two steps from cellulose

• [31][32], has been shown to possess similar physical properties to those of DMF and other dipolar aprotic solvents [31][32]. In addition to its renewability, Cyrene, as yet, has no associated pernicious effects and could potentially represent a direct and functional replacement in many of the

• ][35], Mizoroki–Heck [36][37], Sonogashira [38], Stille [39], Hiyama reactions [40], and hydroformylation reactions [41]. In the current study, we present the use of Cyrene as an alternative solvent (direct DMF replacement) for the Sonogashira reaction, as well as related Cacchi-type annulations [42