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SUBJECTS lithium

Schou ° has reported a reduced choice reaction time, but in our study no significant differences were found in choice reaction time, or informed delay reaction time, between placebo and lithium subjects. Thus, change in reaction time could not account for the reduction in aggressive behavior in this study. [Pg.279]

Gestodene has been prepared in several ways (85). The route that provides the highest yield is shown in Eigure 8. Microbial oxidation of (55) with Penicillium raistrickii results in the 15-alcohol (56). Protection of the alcohol as the acetate (57) and protection of the ketone as a dienolether provides (58). In a one-pot procedure (58) is treated with lithium acetyUde and subjected to a hydrolytic work-up to provide gestodene (54) (86). [Pg.214]

The styrene-diene triblocks, the main subject of this section, are made by sequential anionic polymerisation (see Chapter 2). In a typical system cc-butyl-lithium is used to initiate styrene polymerisation in a solvent such as cyclohexane. This is a specific reaction of the type... [Pg.297]

It is preferable to use ether subjected to final drying by distillation from lithium aluminum hydride. [Pg.49]

The measured relationships between piezoelectric polarization and strain for x-cut quartz and z-cut lithium niobate are found to be well fit by a quadratic relation as shown in Fig. 4.4. In both materials a significant nonlinear piezoelectric effect is indicated. The effect in lithium niobate is particularly notable because the measurements are limited to much smaller strains than those to which quartz can be subjected. The quadratic polynomial fits are used to determine the second- and third-order piezoelectric constants and are summarized in Table 4.1. Elastic constants determined in these investigations were shown in Chap. 2. [Pg.79]

The scope of heteroaryne or elimination-addition type of substitution in aromatic azines seems likely to be limited by its requirement for a relatively unactivated leaving group, for an adjacent ionizable substituent or hydrogen atom, and for a very strong base. However, reaction via the heteroaryne mechanism may occur more frequently than is presently appreciated. For example, it has been recently shown that in the reaction of 4-chloropyridine with lithium piperidide, at least a small amount of aryne substitution accompanies direct displacement. The ratio of 4- to 3-substitution was 996 4 and, therefore, there was 0.8% or more pyridyne participation. Heteroarynes are undoubtedly subject to orientation and steric effects which frequently lead to the overwhelming predominance of... [Pg.152]

The homology between 22 and 21 is obviously very close. After lithium aluminum hydride reduction of the ethoxycarbonyl function in 22, oxidation of the resultant primary alcohol with PCC furnishes aldehyde 34. Subjection of 34 to sequential carbonyl addition, oxidation, and deprotection reactions then provides ketone 21 (31% overall yield from (—)-33). By virtue of its symmetry, the dextrorotatory monobenzyl ether, (/ )-(+)-33, can also be converted to compound 21, with the same absolute configuration as that derived from (S)-(-)-33, by using a synthetic route that differs only slightly from the one already described. [Pg.199]

Short-circuit tests with lithium-ion batteries have been reported recently [35]. This work shows that the separator provides shutdown when the battery is subjected to an external short circuit with the PTC bypassed. The large increase in impedance of the separator is attributed to the temperature rise in the battery. [Pg.561]

The general trend is that boron enolates parallel lithium enolates in their stereoselectivity but show enhanced stereoselectivity. There also are some advantages in terms of access to both stereoisomeric enol derivatives. Another important characteristic of boron enolates is that they are not subject to internal chelation. The tetracoordinate dialkylboron in the cyclic TS is not able to accept additional ligands, so there is no tendency to form a chelated TS when the aldehyde or enolate carries a donor substituent. Table 2.2 gives some typical data for boron enolates and shows the strong correspondence between enolate configuration and product stereochemistry. [Pg.73]

The ester 7-1 gives alternative stereoisomers when subjected to Claisen rearrangement as the lithium enolate or as the silyl ketene acetal. Analyze the respective transition structures and develop a rationale to explain these results. [Pg.609]

Alkenylsilanes can be prepared from aldehydes and ketones using lithio(chloromethyl)trimethylsilane. The adducts are subjected to a reductive elimination by lithium naphthalenide. This procedure is stereoselective for the E-isomer with both alkyl and aryl aldehydes.82... [Pg.813]


See other pages where SUBJECTS lithium is mentioned: [Pg.79]    [Pg.218]    [Pg.305]    [Pg.525]    [Pg.157]    [Pg.382]    [Pg.76]    [Pg.155]    [Pg.174]    [Pg.108]    [Pg.159]    [Pg.176]    [Pg.12]    [Pg.105]    [Pg.235]    [Pg.142]    [Pg.150]    [Pg.201]    [Pg.431]    [Pg.516]    [Pg.519]    [Pg.607]    [Pg.613]    [Pg.650]    [Pg.781]    [Pg.556]    [Pg.251]    [Pg.402]    [Pg.902]    [Pg.538]    [Pg.274]    [Pg.119]    [Pg.57]    [Pg.1010]    [Pg.38]    [Pg.135]    [Pg.79]    [Pg.367]    [Pg.1225]    [Pg.638]   
See also in sourсe #XX -- [ Pg.180 ]




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Cumulative Subject lithium aluminum hydride

Cumulative Subject lithium aluminum hydride modifiers

Lithium aluminum hydride Subject

Lithium diisopropylamide Subject

Lithium enolates Subject

Lithium naphthalenide Subject

Lithium oxide Subject

Subject lithium halides

Subject lithium metal

Subject lithium-based

Subject use of lithium diisopropylamide

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