Coupling of C9
-
14 (4) and C15
-
21 (5a) fragments to produce the
cis-trisubstituted olefin was achieved using Suzuki-type coupling
conditions employed by Marshall (5a/tert-BuLi/B-OMe-9-BBN
added to 4/Cs2CO3/Pd(dppf)2). The terminal (Z)-diene moiety
was attached to aldehyde 10 by using a sequential Nozaki−Hiyama allylation and Peterson olefination sequence; careful
monitoring of the disappearance of both diastereomeric β-hydroxysilanes was found to be essential for achieving a high yield.
In the oxidation of alcohols 12 and 16 to 13 and 7, respectively,
using iodobenzene diacetate and TEMPO, addition of a trace
of water was found to be crucial for complete conversion. The
C8
-
9 (Z)-olefin functionality was introduced on to aldehyde 13
using a Still−Gennari HWE reaction. Subsequent carbamate
installation at C-19 followed by a reduction/oxidation sequence
gave the title fragment C7
-
24 (7) ready to be coupled with the
C1
-
6 fragment, which is described in Part 2 of this series.
Recently, considerable attention has been directed to violence and misbehavior in U.S. schools. In turn, schools have looked for solutions to address such concerns, one of which is the use of law enforcement officers. The aim of this research is to explore how law enforcement officers define their actual roles, as well as their perceived roles in an educational setting. Also, this study examines the process for establishing these roles within the school environment. A total of 26 law enforcement officers were contacted by phone and participated in an in-depth interview. Each interview was transcribed into NVivo, and subsequently coded to identify general themes and common phrases. The findings suggest that officers working in the school environment are taking on many roles, some of which they do not consider appropriate. In addition, who establishes these roles varies considerably. The findings are discussed in terms of their deviation from prior literature as well as needed future research endeavors.
Smith's procedure of preparing fragment C15
-
21 (5) from
common precursor 3 was optimized. The ease of plant operations made this six-step route successful for the production of
several kilograms of this fragment with high purity.
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