Modification of physical properties of poly(L-lactic acid) by addition of methyl-β-cyclodextrin

• Toshiyuki Suzuki,
• Ayaka Ei,
• Yoshihisa Takada,
• Hiroki Uehara,
• Takeshi Yamanobe and
• Keiko Takahashi

Beilstein J. Org. Chem. 2014, 10, 2997–3006, doi:10.3762/bjoc.10.318

• PLLA and enhanced the drawability. Keywords: crystallinity; DSC; methyl-β-cyclodextrin; poly(L-lactic acid); Raman spectroscopy; Introduction Poly(L-lactic acid) (PLLA) has attracted attention because it is a biodegradable polymer derived from carbon-neutral resources. However, its melting point (Tm

• other hand, Raman spectroscopy reveals the vibrational states of functional groups, but not thermal properties because irradiation affects the sample temperature [38]. For exact and expeditious structural analysis, it is important to determine simultaneously the thermal properties and the local

• structure [39][40]. Recently, DSC and Raman spectroscopy (DSC-Raman), which simultaneously measure thermal behavior and Raman vibrational states, was developed. The purpose of this study is to investigate the effects of MeCD on the local structure and physical properties of PLLA by DSC-Raman spectroscopy

Encapsulation of biocides by cyclodextrins: toward synergistic effects against pathogens

• Véronique Nardello-Rataj and
• Loïc Leclercq

Beilstein J. Org. Chem. 2014, 10, 2603–2622, doi:10.3762/bjoc.10.273

• demonstrating the interaction between the hydroxyl groups of the β-CD and the nanoparticles’ surface was confirmed by Raman spectroscopy. Transmission electron microscopy images showed pseudo-spherical nanoparticles (Ø ≈ 28.0 nm). The authors characterized the β-CD layer surrounding the nanoparticles by a novel

Improving the reactivity of phenylacetylene macrocycles toward topochemical polymerization by side chains modification

• Simon Rondeau-Gagné,
• Jules Roméo Néabo,
• Maxime Daigle,
• Katy Cantin and
• Jean-François Morin

Beilstein J. Org. Chem. 2014, 10, 1613–1619, doi:10.3762/bjoc.10.167

• the xerogel state to form polydiacetylenes (PDAs), leading to a significant enhancement of the polymerization yields. The organogels and the PDAs were characterized using Raman spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Keywords: carbon nanomaterials; organogels

• confirm the appearance of polydiacetylene. As shown in Figure 3, the UV–vis spectra shows absorption bands at 600 and 650 nm, associated with the red and blue bands of the PDA chain, respectively [51]. To determine whether all the diyne units of PAM2 reacted during irradiation, Raman spectroscopy was

Raman spectroscopy as a tool for monitoring mesoscale continuous-flow organic synthesis: Equipment interface and assessment in four medicinally-relevant reactions

• Trevor A. Hamlin and
• Nicholas E. Leadbeater

Beilstein J. Org. Chem. 2013, 9, 1843–1852, doi:10.3762/bjoc.9.215

• means of a calibration curve, determine product conversion from Raman spectral data as corroborated by data obtained using NMR spectroscopy. Keywords: flow processing; Raman spectroscopy; reaction monitoring; α,β-unsaturated carbonyl; Introduction Continuous-flow processing is used in the chemical

• interfacing a Raman spectrometer with a scientific microwave unit [31]. This has allowed us to monitor reactions from both a qualitative [32][33][34][35] and quantitative [36][37] perspective. A recent report of the use of Raman spectroscopy for monitoring a continuous-flow palladium-catalyzed cross-coupling

• from the flow cell, the scans were halted. While the product mixture was passing through the flow cell, a drop of the exit stream was removed and an NMR spectrum recorded to obtain product conversion for comparison with data obtained by Raman spectroscopy. NMR conversions were determined by comparing

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

• processes [22][23][24][25]. We will not attempt to cover how digital camera methods in general can be applied to all chemical operations nor will we comment on other in-situ methods of reaction analysis such as UV, IR or Raman spectroscopy as this would constitute too broad a topic. Review From eyes to

Photoionisation of the tropyl radical

• Kathrin H. Fischer,
• Patrick Hemberger,
• Andras Bodi and
• Ingo Fischer

Beilstein J. Org. Chem. 2013, 9, 681–688, doi:10.3762/bjoc.9.77

• ]. The vibrational structure of the cation was examined by IR and Raman spectroscopy [6][7][8]. There are 36 normal modes with 20 distinct frequencies, owing to degeneracy. Of these twenty vibrations, four are IR- and seven Raman-active [9]. In contrast to the cation, the odd-electron neutral tropyl

Spin state switching in iron coordination compounds

• Philipp Gütlich,
• Ana B. Gaspar and
• Yann Garcia

Beilstein J. Org. Chem. 2013, 9, 342–391, doi:10.3762/bjoc.9.39

• -dependent FIR or Raman spectroscopy, one can readily recognize the vibrational bands characteristic of the HS and the LS species as those with decreasing and increasing intensity, respectively, on cooling of the sample [64][65][66][67][68][69][70]. Although not often practiced, one can also derive the spin

• isotopes that have not been accessible with conventional Mössbauer spectroscopy can be used. NIS allows the investigation of vibrational modes and the partial density of states (PDOS) locally, i.e., in the close neighborhood of the Mössbauer probe nucleus. Compared, for instance, to Raman spectroscopy, NIS