The totalsynthesis of protoporphyrin IX and its disodium salt using a new alternative method to the classical MacDonald condensation is reported. The key step is the reaction of the new unsymmetrical diiodo dipyrrylmethane 1 with the known dipyrrylmethane 2. Coupling of the two fragments leads directly to porphyrin 3 without the need of an oxidizing agent. The new methodology is well suited for the
Selective Alkenylation and Hydroalkenylation of Enol Phosphates through Direct CH Functionalization
作者:Xu‐Hong Hu、Xiao‐Fei Yang、Teck‐Peng Loh
DOI:10.1002/anie.201506437
日期:2015.12.14
Rh‐catalyzed direct CH functionalization reaction of enol phosphates was developed. The method is applicable to a variety of coupling partners, including activatedalkenes, alkynes, and allenes, and leads to the formation of various valuable alkenylated and hydroalkenylated enol phosphates through the action of the phosphate directing group. The versatility and utility of the coupling products were demonstrated
Palladium-Catalyzed Additions of Terminal Alkynes to Acceptor Alkynes
作者:Barry M. Trost、Mark T. Sorum、Chuen Chan、Gerd Rühter
DOI:10.1021/ja9624937
日期:1997.1.1
The development of addition reactions wherein the product is the simple sum of the reactants plus anything else (only needed catalytically) constitutes an important goal for enhanced synthetic efficiency. The C−H bond of terminalalkynes (the donor alkynes) can be added to either terminalalkynes (self-coupling) or activated internal alkynes (cross-coupling) (the acceptor alkynes) in the presence of
Process For Preparing Porphyrin Derivatives, Such As Protoporphyrin (IX) And Synthesis Intermediates
申请人:Martin Pierre
公开号:US20080242857A1
公开(公告)日:2008-10-02
The present invention relates to a process for preparing a porphyrin of formula (I), optionally in the form of a salt with an alkali metal and/or in the form of a metal complex:
in which:
R and R′ are as defined in claim
1
,
comprising:
a step of condensation, in an acidic medium, between a dipyrromethane of formula (II):
in which R′b is as defined above for (I),
and a dipyrromethane of formula (III):
in which R″ is as defined in claim
1
, and also the compounds of formula (III).
Stereoselective Synthesis of the C1–C22 Carbon Framework of (−)-Amphidinolide K
作者:Somnath S. Chandankar、Sadagopan Raghavan
DOI:10.1021/acs.joc.9b01248
日期:2019.8.2
Two stereoselective routes to the C7–C22 subunit of amphidinolide K are disclosed. Jacobsen’s hydrolytic kinetic resolution and Sharpless’ asymmetric dihydroxylation reactions have been employed for the construction of the tetrahydrofuran ring. The C10–C11, C16–C17, C9–O, and C18–O bonds have been created using α-chloro sulfide intermediates and [2,3] sigmatropic rearrangement. Marshall’s propargylation