Alkoxy groups, introduction

The introduction of alkoxy groups onto the benzhydryl system leading to a system cleavable by HE was first reported by Walter in 1976 [25] while one additional alkoxy group leads to the Rink linker (12), introduced in 1987 [26]. As quite mild conditions are sufficient for the release of the library components, the Rink resin has effectively been applied to the synthesis of several small molecule libraries [27]. 

The introduction of an alkoxy group into the central benzene ring causes a distinct shift toward orange. A similar bathochromic effect is obtained by replacing this benzene with naphthalene. 

Introduction of an alkoxy group a to the aldehyde results in a dramatic change from endo to exo topology (Figure Si3.8). Here chelation between the bulky catalyst and the aldehyde substituent places them in a cis relationship... 

Thus good yields of p-alkoxy alcdiols can be obtained, albeit as diastereomeric mixtures, but unfortunately hydtoxymercurated alkenes unda similar conditions do not lead to useful products. Despite this iqrparent limitation, alkoxymercuration-oxidative demercuration has been very effective in a number of systems described below, and there is no doubt it is a procedure worth consi ration for hydroxy group introduction. 

Introduction of a 14-Alkoxy Group into Morphinan-6-ones Without 7,8 Double Bond... 

The bathochromic and hyperchromic shifts of n—mi or ti—mi absorbances (Figure 17.5) of the aryl rings caused by the introduction of two alkoxy groups correlated well with the increased photolability of nitroveratryl linkers during 365 nm irradiation. 

Reactions at the C-5 position of the tetracycline molecule have been limited to the introduction of an alkoxy group (42) and the acetylation of the hydroxyl group (43) in 5-hydroxytetracydine. Neither of these modifications improved the biological activity of the molecule. 

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