Radical-mediated dehydrative preparation of cyclic imides using (NH₄)₂S₂O₈–DMSO: application to the synthesis of vernakalant

• Dnyaneshwar N. Garad,
• Subhash D. Tanpure and
• Santosh B. Mhaske

Beilstein J. Org. Chem. 2015, 11, 1008–1016, doi:10.3762/bjoc.11.113

• , hydrothermal cyclization, H2SO4 in acetic acid, PEG-600, silica supported TaCl5, esterification using inorganic base and alkylating agent followed by heating in the presence of tetrabutylammonium bromide, diphenyl 2-oxo-3-oxazolinylphosphonate and Et3N as well as several other conditions have been reported in

Camera-enabled techniques for organic synthesis

• Steven V. Ley,
• Richard J. Ingham,
• Matthew O’Brien and
• Duncan L. Browne

Beilstein J. Org. Chem. 2013, 9, 1051–1072, doi:10.3762/bjoc.9.118

• vessel, and consequently they employed a borescope camera to visualise the interior of the reactor. This allowed the authors to make phase measurements by visual inspection, to discover that with n-propanol as the alkylating agent, the best results for monosubstitution were obtained by using either

Development of peptidomimetic ligands of Pro-Leu-Gly-NH₂ as allosteric modulators of the dopamine D₂ receptor

• Swapna Bhagwanth,
• Ram K. Mishra and
• Rodney L. Johnson

Beilstein J. Org. Chem. 2013, 9, 204–214, doi:10.3762/bjoc.9.24

• oxazolidinones 56 and 57, which served as precursors to the corresponding novel (R,R)-α,α’-biproline 58 and meso-α,α’-biproline 59 [57]. In contrast, the reaction of the more electrophilic alkylating agent glycol bistriflate with the enolate of 30 provided the desired dimer 55, which after acid hydrolysis of the

A ferrocene redox-active triazolium macrocycle that binds and senses chloride

• Nicholas G. White and
• Paul D. Beer

Beilstein J. Org. Chem. 2012, 8, 246–252, doi:10.3762/bjoc.8.25

• , during which time it took on a brown tinge. Methanol (1 mL) was added to quench the alkylating agent, and the mixture was evaporated to dryness under reduced pressure. The crude mixture was purified by preparative thin layer chromatography (silica, eluent: 17:2:1 CH3CN/H2O/sat. KNO3(aq)). The band

• ) was added and the orange solution stirred at room temperature under a nitrogen atmosphere overnight. Methanol (1 mL) was added to quench the alkylating agent, and the mixture was evaporated to dryness under reduced pressure. Purification by preparative thin-layer chromatography (silica, eluent: 10

Fifty years of oxacalix[3]arenes: A review

• Kevin Cottet,
• Paula M. Marcos and
• Peter J. Cragg

Beilstein J. Org. Chem. 2012, 8, 201–226, doi:10.3762/bjoc.8.22

• instead of MeOH) [26], and Yamato later reported a 90% yield [33]. This is in stark contrast to the maximum yield of 25% for the esterification reaction discussed above and points to a subtle, yet essential, difference between the interaction modes of the oxacalixarene, cation and alkylating agent

Fine-tuning alkyne cycloadditions: Insights into photochemistry responsible for the double-strand DNA cleavage via structural perturbations in diaryl alkyne conjugates

• Wang-Yong Yang,
• Samantha A. Marrone,
• Nalisha Minors,
• Diego A. R. Zorio and
• Igor V. Alabugin

Beilstein J. Org. Chem. 2011, 7, 813–823, doi:10.3762/bjoc.7.93

• photochemical process. On the other hand, compound 7, which is unlikely to be a strong alkylating agent in the excited state, was the least-efficient DNA cleaver and did not produce any ds breaks. Interestingly, all three C-lysine conjugates broke DNA more efficiently at lower pH. Effects of radical scavengers

Synthesis of imidazol- 1-yl-acetic acid hydrochloride: A key intermediate for zoledronic acid

• Santosh Kumar Singh,
• Narendra Manne,
• Purna Chandra Ray and
• Manojit Pal

Beilstein J. Org. Chem. 2008, 4, No. 42, doi:10.3762/bjoc.4.42

• and results of earlier reports (step 1 of Method a, b & c, Scheme 1) we chose tert-butyl chloroacetate as an efficient and cheaper (compared to tert-butyl bromoacetate) alkylating agent for 1. Accordingly, compound 2 was prepared by reacting 1 with stoichiometric amount of tert-butyl chloroacetate in