Homolytic substitution at phosphorus for C–P bond formation in organic synthesis

• Hideki Yorimitsu

Beilstein J. Org. Chem. 2013, 9, 1269–1277, doi:10.3762/bjoc.9.143

• Me3M–PPh2 (M = Sn, Si) and V-40 (Table 9) [26]. Secondary and tertiary alkyl iodides participate in the addition reaction while primary alkyl iodide results in direct phosphination prior to the expected addition. Not only acrylate ester but also acrylamide, vinyl sulfone, and acrylonitrile are good

Cascade radical reaction of substrates with a carbon–carbon triple bond as a radical acceptor

• Hideto Miyabe,
• Ryuta Asada and
• Yoshiji Takemoto

Beilstein J. Org. Chem. 2013, 9, 1148–1155, doi:10.3762/bjoc.9.128

• transfer conditions by using isopropyl iodide and Et3B. The reaction of hydroxamate ester 5 did not give the desired product probably due to polymerization of 5 through the labile acrylamide moiety. In contrast, the reaction of 6A–C proceeded effectively to give the cyclic products 9Aa–9Ca in good yields

Total synthesis and biological evaluation of fluorinated cryptophycins

• Christine Weiß,
• Tobias Bogner,
• Benedikt Sammet and
• Norbert Sewald

Beilstein J. Org. Chem. 2012, 8, 2060–2066, doi:10.3762/bjoc.8.231

• homoallyl alcohol 16. The magnesium bromide diethyl etherate mediated allylation proceeded under substrate control and with complete diastereoselectivity [23][32]. Cross-metathesis of homoallyl alcohol 16 with the unit B derived acrylamide 17 provided the α,β-unsaturated δ-hydroxy carboxamide 18 (Scheme 2

• ). In order to bring about complete metathesis of 16, the acrylamide 17 had to be employed in 1.2-fold excess, which resulted in a contamination of the cross-metathesis product 18 with minor amounts of the homo-coupling product 23. The latter could not be separated by flash chromatography on this stage

Interaction of cyclodextrins with pyrene-modified polyacrylamide in a mixed solvent of water and dimethyl sulfoxide as studied by steady-state fluorescence

• Akihito Hashidzume,
• Yongtai Zheng and
• Akira Harada

Beilstein J. Org. Chem. 2012, 8, 1312–1317, doi:10.3762/bjoc.8.150

• hydrochloride was purchased from Sigma-Aldrich Co. Ltd. Acryloyl chloride was obtained from Tokyo Chemical Industry Co. Ltd. Triethylamine, acrylamide (AAm), ammonium peroxodisulfate (APS), acetone, methanol, DMSO (spectroscopic grade), NaHCO3, and NaOH were purchased from Nacalai Tesque Inc. N,N

Design of a novel tryptophan-rich membrane-active antimicrobial peptide from the membrane-proximal region of the HIV glycoprotein, gp41

• Evan F. Haney,
• Leonard T. Nguyen,
• David J. Schibli and
• Hans J. Vogel

Beilstein J. Org. Chem. 2012, 8, 1172–1184, doi:10.3762/bjoc.8.130

• particular peptide in aqueous buffer. Therefore, the smaller blue shifts for gp41w can be attributed to the peptide dissociating from the oligomeric form followed by peptide insertion into the bilayer. Acrylamide quenching experiments were performed for the four peptides to examine the accessibility of the

• Trp fluorophores in the various membrane environments. If a Trp side chain inserts into the hydrophobic core of the bilayer, it becomes less accessible to the effects of the soluble acrylamide quencher. The quenching of Trp fluorescence is directly related to the concentration of quencher, so a

• titration with the neutral acrylamide allows for the calculation of the Stern–Volmer constant (Ksv), which quantitatively measures the accessibility of the Trp residues in various lipid environments. The Ksv values for the gp41w peptides are summarized in Figure 3. Consistent with the other fluorescence

Miniemulsion polymerization as a versatile tool for the synthesis of functionalized polymers

• Daniel Crespy and
• Katharina Landfester

Beilstein J. Org. Chem. 2010, 6, 1132–1148, doi:10.3762/bjoc.6.130

• -soluble, surface active, and oil-soluble initiators were employed to initiate the polymerizations as shown in Figure 1. Oil-soluble initiators were found to give a higher yield of copolymers of acrylamide and methyl methacrylate with a low extent of blockiness than with a water-soluble initiator or

• surface active initiator. By contrast, the surface active polyethylene glycol azo-initiator yielded polymers almost free of homopolymers with a low blockiness when acrylamide and styrene were copolymerized. Wu et al. used the same principle but with monomers having the ability to copolymerize alternately

• the encapsulation of hydrophobic substances could be obtained. Capsules could be also obtained when methacrylic acid was used instead of acrylic acid [31]. Wu and Schork investigated the copolymerization between the functional n-methylol acrylamide and vinyl acetate in batch and semi-batch processes

RAFT polymers for protein recognition

• Alan F. Tominey,
• Julia Liese,
• Sun Wei,
• Klaus Kowski,
• Thomas Schrader and
• Arno Kraft

Beilstein J. Org. Chem. 2010, 6, No. 66, doi:10.3762/bjoc.6.66

• from earlier work with linear polymers and microgels [9][15][16]: Sodium methacrylate (2) (S), polymerizable tetrazolate 3 (T) and bisphosphonate 4 (B). These anionic comonomers were directly copolymerized with NIPAM and a hydrophobic acrylamide. The latter carried cyclohexyl (CH), benzyl (BN) or octyl

N-alkyl-N-(phosphonoethyl) substituted (meth)acrylamides – new adhesive monomers for self-etching self-priming one part dental adhesive

• Joachim E. Klee and
• Uwe Lehmann

Beilstein J. Org. Chem. 2009, 5, No. 72, doi:10.3762/bjoc.5.72

• spectroscopy as well as refractive index and viscosity. The phosphonoethyl substituted (meth)acrylamide monomers show improved hydrolytic stability compared to carboxylic esters. The highest stability was found for the phosphonoethyl substituted acrylamide monomers. Acrylamides have a larger polymerization

• -methylacrylamidomethyl)benzylphosphonic acid [2] and a bis(meth)acrylamide comprising one phosphoric acid moiety [3] have been prepared and were investigated for a dental adhesive. Furthermore, (meth)acrylamides with one [4][5][6][7][8] or two [7][8][9] phosphonic acid groups were suggested as hydrolytically stable

• acid ethyl ester with trimethylsilyl bromide (Scheme 1, Table 1). (Meth)acrylamides 3a and 3b were prepared by addition of vinylphosphonic acid ethyl ester to acrylamide and methacrylamide respectively and the same procedure for methanolysis of the phosphonic acid ethyl ester as that described above