國立高雄大學圖資館 |

Language: English

Back

Palladium catalyzed asymmetric allylic alkylation (AAA) of prochiral nucleophiles :Efforts toward the synthesis of erinacine A.

Record Type:	Electronic resources : Monograph/item
Title/Author:	Palladium catalyzed asymmetric allylic alkylation (AAA) of prochiral nucleophiles :
Reminder of title:	Efforts toward the synthesis of erinacine A.
Author:	Schroeder, Gretchen Marie.
Description:	722 p.
Notes:	Adviser: Barry M. Trost.
Notes:	Source: Dissertation Abstracts International, Volume: 64-03, Section: B, page: 1252.
Contained By:	Dissertation Abstracts International64-03B.
Subject:	Chemistry, Organic.
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3085366
ISBN:	0496331736

Palladium catalyzed asymmetric allylic alkylation (AAA) of prochiral nucleophiles :Efforts toward the synthesis of erinacine A.
Schroeder, Gretchen Marie.

Palladium catalyzed asymmetric allylic alkylation (AAA) of prochiral nucleophiles :Efforts toward the synthesis of erinacine A. [electronic resource] - 722 p.

Adviser: Barry M. Trost.

Thesis (Ph.D.)--Stanford University, 2003.

Application of the palladium catalyzed AAA to the synthesis of barbituric acid derivatives was explored. Palladium catalyzed AAA using prochiral electrophiles allowed for the synthesis of cyclopentobarbital and pentobarbital in 91% and 81% ee respectively. Palladium catalyzed AAA of prochiral nucleophiles to give enantioenriched barbiturates proved more difficult and gave the corresponding alkylated products in poor ee (37%).

ISBN: 0496331736Subjects--Topical Terms:

193634
Chemistry, Organic.

Palladium catalyzed asymmetric allylic alkylation (AAA) of prochiral nucleophiles :Efforts toward the synthesis of erinacine A.
LDR:03600nmm _2200289 _450 001 161918
005 20051017073351.5
008 230606s2003 eng d
020 $a 0496331736
035 $a 00148419
035 $a 161918
040 $a UnM $c UnM
100 0 $a Schroeder, Gretchen Marie. $3 227011
245 1 0 $a Palladium catalyzed asymmetric allylic alkylation (AAA) of prochiral nucleophiles : $b Efforts toward the synthesis of erinacine A. $h [electronic resource]
300 $a 722 p.
500 $a Adviser: Barry M. Trost.
500 $a Source: Dissertation Abstracts International, Volume: 64-03, Section: B, page: 1252.
502 $a Thesis (Ph.D.)--Stanford University, 2003.
520 # $a Application of the palladium catalyzed AAA to the synthesis of barbituric acid derivatives was explored. Palladium catalyzed AAA using prochiral electrophiles allowed for the synthesis of cyclopentobarbital and pentobarbital in 91% and 81% ee respectively. Palladium catalyzed AAA of prochiral nucleophiles to give enantioenriched barbiturates proved more difficult and gave the corresponding alkylated products in poor ee (37%).
520 # $a Asymmetric alkylation of simple ketone enolates to generate quaternary chiral centers was investigated. The complex generated from palladium(0) and a chiral ligand synthesized from 1,2-diaminocyclohexane and 2-diphenylphosphinobenzoic acid catalyzed the alkylation and gave the quaternary substituted products with excellent enantioselectivity. Lithium enolates of 2-alkylcycloalkanones and potassium enolates of 2-arylcycloalkanones gave the best results. For alpha-aryl ketones, a naphthyl derived chiral ligand was required for good enantioselectivity.
520 # $a The erinacines present formidable synthetic targets due to their 5,6,7-tricyclic ring system, oxidation state, and quaternary chiral centers. Efforts were directed toward the total synthesis of erinacine A, a potent stimulator of nerve growth factor synthesis. All of the stereocenters were set from an enantioenriched alpha-quaternary substituted cyclopentanone which was itself a product of the palladium catalyzed AAA of a prochiral ketone enolate. The six membered ring was constructed with a palladium catalyzed reductive diyne cyclization while the seven membered ring was formed in a palladium catalyzed [4+3] TMM reaction. The TMM cycloaddition gave the tricyclic core of erinacine A in just thirteen steps. The second quaternary chiral center was set by an intramolecular Stork radical cyclization. An advanced intermediate was ultimately constructed which possessed all of the carbon atoms of erinacine A. Adjustment of the oxidation state remains to be completed.
520 # $a The palladium catalyzed AAA of cyclic 1,2-diketones was examined. The corresponding O-alkylated products were obtained in excellent regio- and enantioselectivity. Acyclic and cyclic allylic carbonates as well as vinyl epoxides functioned well as electrophiles. Claisen rearrangement of the allylic enol ethers using catalytic HoFOD transferred the stereochemistry from oxygen to carbon with outstanding chirality transfer and complete diastereoselectivity. This two step AAA/Claisen protocol constitutes a second approach toward synthesizing alpha-quaternary substituted cycloalkanones.
590 $a School code: 0212.
650 # 0 $a Chemistry, Organic. $3 193634
710 0 # $a Stanford University. $3 212607
773 0 # $g 64-03B. $t Dissertation Abstracts International
790 $a 0212
790 1 0 $a Trost, Barry M., $e advisor
791 $a Ph.D.
792 $a 2003
856 4 0 $u http://libsw.nuk.edu.tw/login?url=http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3085366 $z http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3085366