Insertion of an Alkene into an Ester: Intramolecular Oxyacylation Reaction of Alkenes through Acyl CO Bond Activation
作者:Giang T. Hoang、Venkata Jaganmohan Reddy、Huy H. K. Nguyen、Christopher J. Douglas
DOI:10.1002/anie.201005767
日期:2011.2.18
Atom economy and esters: compatible now! The first catalytic insertion of a CC bond into an acyl CO bond was achieved using rhodium catalysts (see scheme). The products are β‐alkoxy ketones with a fully substituted carbon center. Quinoline chelating groups were employed to stabilize the Rh‐alkoxide intermediate.
ring: Annulated cyclohexenes were synthesized by using the title reaction with the cationicrhodium(I)/(R)‐H8‐binapcomplex as a catalyst. In this catalysis, regioselective insertion of the acrylamide into a rhodacyclopentene intermediate and the coordination of the carbonyl group of the acrylamide to the cationicrhodium center suppress the undesired β‐hydride elimination.
Cooperative Catalysis Approach to Intramolecular Hydroacylation
作者:Evgeny V. Beletskiy、Ch. Sudheer、Christopher J. Douglas
DOI:10.1021/jo300779q
日期:2012.7.20
examples of hydroacylation to form six- and seven-membered ring ketones require either embedded chelating groups or other substrate design strategies to circumvent competitive aldehydedecarbonylation. A cooperative catalysis strategy enabled intramolecular hydroacylation of disubstituted alkenes to form seven- and six-membered rings without requiring substrate-embedded chelating groups.
[1,5]-Anion Relay/[2,3]-Wittig Rearrangement of 3,3-Bis(silyl) Allyl Enol Ethers: Synthesis of Useful Vinyl Bis(silane) Species
作者:Xianwei Sun、Jian Lei、Changzhen Sun、Zhenlei Song、Linjie Yan
DOI:10.1021/ol300004b
日期:2012.2.17
The [1,5]-anion relay/[2,3]-Wittigrearrangement of 3,3-bis(silyl) enol allyl ethers has been developed. This reaction provides an efficient method to synthesize versatile vinyl bissilanes, which can be transformed into trisubstituted vinylsilanes through a [1,4]-Brook rearrangement/alkylation protocol using a wide range of electrophiles.
FLUORINATED DIHYDROTETRABENAZINE ETHER IMAGING AGENTS AND PROBES
申请人:Amarasinghe Kande Kankanamalage Dayarathna
公开号:US20090110636A1
公开(公告)日:2009-04-30
The present invention provides novel fluorinated ether compounds having structure I
wherein R
1
is a C
2
-C
10
fluorinated aliphatic radical; R
2
is a C
1
-C
10
aliphatic radical, or a C
3
-C
10
cycloaliphatic radical; R
3
is hydrogen or a C
1
-C
10
aliphatic radical; and R
4
is hydrogen or a C
1
-C
10
aliphatic radical. The fluorinated ether compounds are provided in both racemic and enantiomerically enriched forms and may comprise either or both of fluorine-18 and fluorine 19. The fluorinated ether compounds are shown to possess high affinity for VMAT-2, a biomarker implicated in human diabetes. The fluorinated ether compounds comprising a fluorine-18 group are useful as PET imaging agents targeting the VMAT-2 biomarker. The non-radiolabeled fluorinated ether compounds are useful as probes for the discovery of PET imaging agents.