13395-34-1Relevant articles and documents
Tridentate Directing Groups Stabilize 6-Membered Palladacycles in Catalytic Alkene Hydrofunctionalization
O'Duill, Miriam L.,Matsuura, Rei,Wang, Yanyan,Turnbull, Joshua L.,Gurak, John A.,Gao, De-Wei,Lu, Gang,Liu, Peng,Engle, Keary M.
, p. 15576 - 15579 (2017)
Removable tridentate directing groups inspired by pincer ligands have been designed to stabilize otherwise kinetically and thermodynamically disfavored 6-membered alkyl palladacycle intermediates. This family of directing groups enables regioselective remote hydrocarbofunctionalization of several synthetically useful alkene-containing substrate classes, including 4-pentenoic acids, allylic alcohols, homoallyl amines, and bis-homoallylamines, under Pd(II) catalysis. In conjunction with previous findings, we demonstrate regiodivergent hydrofunctionalization of 3-butenoic acid derivatives to afford either Markovnikov or anti-Markovnikov addition products depending on directing group choice. Preliminary mechanistic and computational data are presented to support the proposed catalytic cycle.
Synthesis of Cannabinoid Model Compounds. Part 2): (3R,4R)-δ1(6)-Tetrahydrocannabinol-5"-oic Acid and 4"(R,S)-Methyl-(3R,4R)-δ1(6)-Tetrahydrocannabinol-5"-oic Acid
Franke, Ingo,Binder, Michael
, p. 2508 - 2514 (1980)
Two novel cannabinoid model compounds, (3R,4R)-Δ1(6)-tetrahydrocannabinol-5"-oic acid (22) and 4"(R,S)-methyl-(3R,4R)-Δ1(6)-tetrahydrocannabinol-5"-oic acid (23) were synthesized by acid-catalyzed condensation of (+)-trans-p-mentha-2,8-dien-1-ol (1) with the substituted resorcinols 18 and 19 obtained by a Wittig reaction between 3,5-bis(benzyloxy)benzaldehyde (7) and methyl 4-bromobutanoate (10) or methyl 4-bromo-2(R,S)-methylbutanoate (11) resp. with subsequent hydrogenation.The resulting methyl esters 20 and 21 were hydrolyzed to give acids 22 and 23.
Stereospecific radiosynthesis of 3-fluoro amino acids: Access to enantiomerically pure radioligands for positron emission tomography
Alluri, Santosh R.,Riss, Patrick J.
supporting information, p. 2219 - 2224 (2018/04/05)
A variety of substituted non-racemic aziridine-2-carboxylates equivalent to amino acids were prepared and subjected to ring opening reaction by [18F/19F]fluoride. The regio and stereospecific ring opening depends on the substituents on the nitrogen as well as both the carbons of aziridines. The applicability of the methods to afford access to 3-[18F/19F]fluoro amino acids are illustrated.
C(alkenyl)-H Activation via Six-Membered Palladacycles: Catalytic 1,3-Diene Synthesis
Liu, Mingyu,Yang, Pusu,Karunananda, Malkanthi K.,Wang, Yanyan,Liu, Peng,Engle, Keary M.
supporting information, p. 5805 - 5813 (2018/05/14)
A catalytic method to prepare highly substituted 1,3-dienes from two different alkenes is described using a directed, palladium(II)-mediated C(alkenyl)-H activation strategy. The transformation exhibits broad scope across three synthetically useful substrate classes masked with suitable bidentate auxiliaries (4-pentenoic acids, allylic alcohols, and bishomoallylic amines) and tolerates internal nonconjugated alkenes, which have traditionally been a challenging class of substrates in this type of chemistry. Catalytic turnover is enabled by either MnO2 as the stoichiometric oxidant or co-catalytic Co(OAc)2 and O2 (1 atm). Experimental and computational studies were performed to elucidate the preference for C(alkenyl)-H activation over other potential pathways. As part of this effort, a structurally unique alkenylpalladium(II) dimer was isolated and characterized.
