Oxacycle Synthesis via Intramolecular Reaction of Carbanions and Peroxides
作者:Rachel Willand-Charnley、Benjamin W. Puffer、Patrick H. Dussault
DOI:10.1021/ja5026276
日期:2014.4.23
The intramolecular reaction of dialkyl peroxides with carbanions, generated via chemoselective metal-heteroatom exchange or deprotonation, provides a newapproach to cyclicethers. Applied in tandem with C–C bond formation, the strategy enables a one-step annelation to form oxaospirocycles.
New approaches to the synthesis of spiro-peroxylactones
作者:Kevin J. McCullough、Hidekazu Tokuhara、Araki Masuyama、Masatomo Nojima
DOI:10.1039/b300342f
日期:2003.4.23
Ozonolysis of (alkenyldioxy)cyclododecyl hydroperoxides in trifluoroethanol gave a separable mixture of the corresponding α-hydroperoxy- and α-hydroxy-substituted spiro-tetraoxacycloalkanes with ring sizes in the range 7–12. Dehydration of the hydroperoxides or oxidation of the hydroxy-compounds afforded the corresponding peroxylactones. The solid-state structure of 1,2,6,7-tetraoxaspiro[7.11]nonadecan-3-one was determined by X-ray crystallographic analysis.
Stereoselective Preparation of Dienyl Zirconocene Complexes via a Tandem Allylic C−H Bond Activation-Elimination Sequence
作者:Nicka Chinkov、Swapan Majumdar、Ilan Marek
DOI:10.1021/ja036751t
日期:2003.10.1
zirconocene derivatives were easily prepared, as unique geometrical isomers, from simple non-conjugated unsaturated enolethers with (1-butene)ZrCp2 complexes. This new methodology is based on a tandem allylic C-H bond activation-elimination sequence and the mechanism has been mapped out by deuterium labeling experiments. The stereochemical outcome of this process was determined by addition of several electrophiles
The present invention provides novel benzopyran compounds, pharmaceutically acceptable salts thereof and stereoisomers thereof where the benzopyran compounds of the invention are compounds according to Formula I:
The present invention further provides pharmaceutical compositions which possess anti-estrogenic activity and comprise at least one benzopyran compound of the invention and a method of treating breast cancer by administration of an effective amount of a benzopyran compound provided by the present invention.
Catalytic asymmetric reductive addition of olefins to aldehydes mediated by boron and zinc organometallics
作者:Lothar Schwink、Paul Knochel
DOI:10.1016/0040-4039(94)88412-9
日期:1994.11
A procedure involving a hydroboration, boron-zinc exchange and asymmetricaddition to an aldehyde allows the reductiveaddition of olefins to aldehydes in 50–96 % ee. A short and efficient 3 step synthesis of ginnol (61 % overall yield, 92 % ee) demonstrates the synthetic utility of the method.