Figure 6a shows the competing transition states of C−C bond activation that determine the regioselectivity. The C−C bond cleavage, along with carbenoid formation, can occur at the internal carbon through transition state TS5, or at the external carbon via transition state TS5*. TS5* is ...
i.e. on the neutron rich side of the line of stability, half-life data are generally better known and the respective number ofT1/2determinations is larger. This is especially true for isotopes of the actinide series, where large effort has been put to improve decay data for the nuclear...
Evaluate the structure and determine the number of Sp^{2} Sp^{3}hybridized carbons present. Dehydration of 1-methylcyclohexanol might lead to either of two isomeric alkenes, 1-methylcyclohexene or methylenecyclohexane. How could you use NMR spectroscopy (both ...
aThe m6A nucleobase shows a 20:1 preference for thesynisomer due to unfavorable steric interactions (shown in dashed red lines) in theantiisomer12,25. In a duplex, thesynisomer impedes Watson–Crick pairing, and theantiisomer becomes the dominant form.bApparent annealing (kon) and melting (ko...
After the synthesis of a new target energetic compound, it is very useful to experimentally determine both its real density and the enthalpy of formation, and use these data to adjust the contributions of structural units. 2.1. Frameworks of HEDMs Most traditional energetic materials derive their ...
atωGS = 0 when the RF field is on resonance with the GS. The dependencies ofR2 + Rex(R1ρ) or the GS signal intensity (CEST) onωSLandωRFcan be fit to the Bloch–McConnell (B–M) equations32describing N-site exchange to determine exchange parameters of interest (see below...
The most stable conformer has been detected as well as the 1313C monosubstituted isotopologues in natural abundance and the 1818O enriched water species, allowing to determine the nitrogen nuclear quadrupole coupling constants and the molecular structure in the vibrational ground state. The molecule ...
The aim of this study was to detect and identify the volatile compounds in coffee that was obtained in defect roast processes versus standard roasting and to determine the type and strength of the correlations between the roast defects and the volatile compound profile in roasted coffee beans. In...
Apart from Al2O3, which was ca. 90% selective for retro-Prins products, the rest of the oxides were more selective than H-ZSM5 for 1,3-butadiene. Adding to its high selectivity for dienes, ZrO2is also highly selective for a single diene isomer when multiple dienes can form (C5+) [...
Further refinement of the structure-activity relationship within this series is underway, with 2 recent analogs of Genz-667348 undergoing further testing to determine if they represent suitable candidates for preclinical development [201]. 5.5.4. Anti-sequestration compounds—An interesting possibility In...