A series of anisoles are complexed by pentaammineosmium(II),
and the resulting 5,6-η2-anisole
complexes are treated with activated olefins or acetals in the presence
of triflic acid to form 4H-anisolium
complexes. These intermediates are capable of undergoing inter- or
intramolecular nucleophilic addition
reactions at C3, and 2-methoxy-1,3-cyclohexadiene complexes are formed.
These complexes are readily
converted into functionalized cyclohexenones, cyclohexadienes, and
cyclohexenes. When BF3·OEt2 is
used,
it is possible to form a 4H-anisolium complex with a pendent
boron enolate, which can ultimately undergo
intramolecular addition to C1 to form the corresponding [4 + 2]
cycloadduct. For cases in which an activated
alkyne is added to a C4-alkylated anisole, a migration of the vinyl
group occurs, leading to 4-methyl-3-vinylanisoles.
The Fuglevand model is often used to address challenging questions in neurophysiology; however, there are elements of the neuromuscular system unaccounted for in the model. For instance, in some muscles, slow and fast motor units (MUs) tend to reside deep and superficially in the muscle, respectively, necessarily altering the development of surface electromyogram (EMG) power during activation. Thus, the objective of this study was to replace the randomized MU territory (MUT) placement algorithm in the Fuglevand model with an optimized method capable of reflecting these observations. To accomplish this, a weighting term was added to a previously developed optimization algorithm to encourage regionalized MUT placement. The weighting term consequently produced significantly different muscle fibre type content in the deep and superficial portions of the muscle. The relation between simulated EMG and muscle force was found to be significantly affected by regionalization. These changes were specifically a function of EMG power, as force was unaffected by regionalization. These findings suggest that parameterizing MUT regionalization will allow the model to produce a larger variety of EMG-force relations, as is observed physiologically, and could potentially simulate the loss of specific MU types as observed in ageing and clinical populations.
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