Remote induction

Besides a chiral remote induction for glycosidation, other glycosidic sugar-fused lactones have been also directly used as saccharidic delivery synthons. 

SMPs have most notably been promoted because of their potential in minimally invasive surgery, where a compacted device could be passed through a smaller incision and deployed to its full shape once inside the body [40]. For biomedical devices, the heating of polymer to activate SMEs has been proposed by body, temperature, optical/laser heating, and remote inductive heating [41]. As each of these thermal activation methods is possible within the body, control over SMP geometry is possible with implantable devices. 

Carver JC, Gray RC, Hercules DM (1974) Remote inductive effects evaluated by X-ray photoelectron spectroscopy. J Am Chem Soc 96 6851-6856... 

The greater positive character hence the increased acidity of the O—H proton of 2 2 2 tnfluoroethanol can be seen m the electrostatic potential maps displayed m Figure 1 8 Structural effects such as this that are transmitted through bonds are called indue tive effects A substituent induces a polarization m the bonds between it and some remote site A similar inductive effect is evident when comparing acetic acid and its trifluoro derivative Trifluoroacetic acid is more than 4 units stronger than acetic acid... 

Closely related to the inductive effect and operating in the same direction is the field effect In the field effect the electronegativity of a substituent is communicated not by successive polarization of bonds but via the medium usually the solvent A substituent m a molecule polarizes surrounding solvent molecules and this polarization is transmit ted through other solvent molecules to the remote site... 

The very low Hg concentration levels in ice core of remote glaciers require an ultra-sensitive analytical technique as well as a contamination-free sample preparation methodology. The potential of two analytical techniques for Hg determination - cold vapour inductively coupled plasma mass spectrometry (CV ICP-SFMS) and atomic fluorescence spectrometry (AFS) with gold amalgamation was studied. 

In earlier years, to reach a remote area, where. separate telephone lines had not been laid it was normal practice to rttn them through the same poles as the HT power distribution lines (generally 11-33 kV). This was particularly true of internal communications of the electricity companies for ease of operation and to save costs and time. This commitnication was known as the magneto-telephone system. But the proximity of telephone lines to power lines adversely affected the performance of the telephone lines due to generation of overvoltages (Chapter 20) and eleetrical interferences (conductive and inductive interferences, discussed later) on the telephone lines by the power lines.. Some of these interferenees, particularly system harmonics, had the same frequency as the audio frequency of the telephone lines and alTected their audio quality. 

Induction terminal unit An air terminal assembly which by virtue of the configuration of the primary air inlet(s) within the unit can induce secondary air from the surrounding atmosphere before being discharged to the treated space. The tlow rate of the primary air may or may not be variable. The inlet aperture(s) for the secondary air may be fixed or adjustable by means of manual remote control. 

Remote asymmetric induction using chiral sulfoxides, derivatives of furan, thiophene, and pyrrole 98YGK798. 

In order to use Eqs. (2.6.1) and (2.6.2) to estimate the sensitivity gain obtained by remote detection, knowledge of the relative sensitivity of the detector and the encoding circuit, A, is required. Here we discuss the sensitivity of an rf coil detector as an example, because all the experiments presented in this text use inductive detection at high field. The signal-to-noise ratio of inductive NMR detection can be approximated by the following simplified equation [12] ... 

There was a substantial electronic influence with electron-withdrawing substituents decreasing enantioselectivity. Interestingly, steric bulkiness at this remote part of the molecule was found to be highly effective for asymmetric induction. The bulky ANM group provided 97% ee with a high isolated yield. 

In entry 15 of Table 21.10, it is noted that even a remote hydroxyl group directed hydrogenation by the cationic [Rh(diphos-4)(nbd)]+ catalyst to afford a moderate diastereoselectivity (80 20) [23]. This is an interesting example of long-range 1,5-asymmetric induction. 

The asymmetric induction cannot be explained simply by steric interaction because the R group in the aldehyde is far too remote to interact with the tartrate ester. In addition, the alkyl group present in the tartrate ligand seems to have a relatively minor effect on the overall stereoselectivity. It has thus been proposed that stereoelectronic interaction may play an important role. A more likely explanation is that transition state A is favored over transition state B, in which an n n electronic repulsion involving the aldehyde oxygen atom and the /Mace ester group causes destabilization (Fig. 3-6). This description can help explain the stereo-outcome of this type of allylation reaction. 

Almost 50 years ago, Cram outlined a rule (Cram s rule), which proved to be fruitful in understanding, predicting, and controlling diastereoselectivity induced by a remote stereocenter [258,259], Numerous examples of 1,2 induction have confirmed over the time the predictive character of this rule [260], Afterwards, other important contributions of Felkin and coworkers and Anh... 

Remote steric effects have also been noted to play an unanticipated role in the sense of asymmetric induction. This is apparent from related condensations carried out on aldehydes 106 (26) and 107 (eqs. [76]-[78]) (26,92). Other examples illustrating the influence of remote structural perturbations on the carbonyl addition process have been observed in these laboratories. The addition of the lithio benzoxazole 110 to aldehyde 108 proceeded with good Cram diastereoface selection (95a), whereas the same nucleophilic addition to aldehyde 109 was stereorandom (95b). 

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