Synthesis of bis(3-{[2-(allyloxy)ethoxy]methyl}-2,4,6-trimethylbenzoyl)(phenyl)phosphine oxide – a tailor-made photoinitiator for dental adhesives

• Norbert Moszner,
• Iris Lamparth,
• Jörg Angermann,
• Urs Karl Fischer,
• Frank Zeuner,
• Thorsten Bock,
• Robert Liska and
• Volker Rheinberger

Beilstein J. Org. Chem. 2010, 6, No. 26, doi:10.3762/bjoc.6.26

• phenylphosphine dilithium solution was then added to a THF solution of 2. THF was evaporated from the intermediate bis(3-{[2-(allyloxy)ethoxy]methyl}-2,4,6-trimethylbenzoyl)(phenyl)phosphine solution, the residue dissolved in toluene and oxidized with a 30 wt % hydrogen peroxide solution at 70 °C. After column

• ]methyl}-2,4,6-trimethylbenzoyl)(phenyl)phosphine oxide For this stage all manipulations were carried out in brown glass apparatus or under yellow light. The residue from the latter step was dissolved in toluene (40 mL). Hydrogen peroxide solution (30%, 4.17 g, 36.8 mmol) was added dropwise under vigorous

On the functionalization of benzo[e][2,1]thiazine

• Kirill Popov,
• Tatyana Volovnenko and
• Julian Volovenko

Beilstein J. Org. Chem. 2009, 5, No. 42, doi:10.3762/bjoc.5.42

• oxidizing agents. Thus, oxidants such as sodium dichromate and potassium permanganate did not transform 1 into the corresponding carboxylic acids. Attempted oxidation of compounds 1 with hydrogen peroxide, peroxyacetic acid and m-chloroperoxybenzoic acid (mCPBA) was also unsuccessful. The desired oxidation

Mitomycins syntheses: a recent update

• Jean-Christophe Andrez

Beilstein J. Org. Chem. 2009, 5, No. 33, doi:10.3762/bjoc.5.33

• in 46% overall yield. Interestingly, oxidation with hydrogen peroxide gave predominantly the N-allylic system rather than the vinylic one. This is in accordance with the precedent established by the laboratory of K.B. Sharpless [80][81]. The overall yield from diazo-ester 67 was only 2% and was

The development and evaluation of a continuous flow process for the lipase- mediated oxidation of alkenes

• Charlotte Wiles,
• Marcus J. Hammond and
• Paul Watts

Beilstein J. Org. Chem. 2009, 5, No. 27, doi:10.3762/bjoc.5.27

• lipase B, Novozym® 435, in a preliminary investigation into the development of a continuous flow reactor capable of performing the chemo-enzymatic oxidation of alkenes in high yield and purity, utilising the commercially available oxidant hydrogen peroxide (100 volumes). Initial investigations focussed

• ; hydrogen peroxide; lipase; micro reactor; Novozym® 435; peracids; Introduction In addition to their synthetic value as intermediates in the preparation of diols, alcohols, hydroxyesters and alkenes, epoxides are a key raw material in many industrial processes, finding application in adhesives, polymers

• situ generated peracids derived from formic acid or acetic acid (1)/hydrogen peroxide (2). As H2O2 (2) is itself not sufficiently electrophilic to epoxidise a non-conjugated double bond directly, its use in the formation of a peracid has afforded a route to the epoxidation of alkenes in the presence of

Efficient 1,4-addition of α-substituted fluoro(phenylsulfonyl)methane derivatives to α,β-unsaturated compounds

• G. K. Surya Prakash,
• Xiaoming Zhao,
• Sujith Chacko,
• Fang Wang,
• Habiba Vaghoo and
• George A. Olah

Beilstein J. Org. Chem. 2008, 4, No. 17, doi:10.3762/bjoc.4.17

• . We first began with the preparation of nitro, cyano, ester, or acetyl-substituted (phenylsulfonyl)methanes from the corresponding (phenylthio)methane derivatives, the precursors of α-substituted fluoro(phenylsulfonyl)methane derivatives. Oxidation of (nitromethyl)(phenyl)sulfide with aqueous hydrogen

• peroxide [H2O2, 30% (wt)] was attempted in acetic acid at room temperature. Tuning the conditions by using 4-fold excess of H2O2 afforded 90% yield of (nitromethylsulfonyl)benzene overnight (Table 1, entry 1) [26][27][28]. 2a–c and 2e were prepared in 76–91% yields under the optimized condition and used

The Elbs and Boyland- Sims peroxydisulfate oxidations

• E. J. Behrman

Beilstein J. Org. Chem. 2006, 2, No. 22, doi:10.1186/1860-5397-2-22

• , although they obtained evidence for a peroxide, isolated only phenol (in substantial yield). Heller and Weiler [18] investigated a more stable analog, namely p-nitrophenyl hydroperoxide formed by ipso displacement of a nitro group from p-dinitrobenzene by the hydrogen peroxide anion.p-Nitrophenyl

The vicinal difluoro motif: The synthesis and conformation of erythro- and threo- diastereoisomers of 1,2-difluorodiphenylethanes, 2,3-difluorosuccinic acids and their derivatives

• David O'Hagan,
• Henry S. Rzepa,
• Martin Schüler and
• Alexandra M. Z. Slawin

Beilstein J. Org. Chem. 2006, 2, No. 19, doi:10.1186/1860-5397-2-19

• lead to poor conversions and a complex product mixture. As an alternative strategy ozonolysis in acetic acid, with a hydrogen peroxide work-up was explored [27][28], and this proved successful as illustrated in Scheme 8. For example, reaction of a 4:1 mixture of erythro- and threo- 13 led to the