cas 5406-86-0, 2-(4-tert-Butylphenyl)ethanol

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Design, synthesis, and evaluation of opioid analogues with non-peptidic β-turn scaffold: Enkephalin and endomorphin mimetics
We have identified a μ-selective opioid receptor agonist without a cationic amino group in the molecule from libraries of bicyclic β-turn peptidomimetics. The biologically active conformation of the lead is proposed to mimic an endomorphin type III 4 → 1
Eguchi, Masakatsu,Shen, Richard Y. W.,Shea, J. Paul,Lee, Min S.,Kahn, Michael
p. 1395 - 1398
(2002)
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Erbium-Catalyzed Regioselective Isomerization-Cobalt-Catalyzed Transfer Hydrogenation Sequence for the Synthesis of Anti-Markovnikov Alcohols from Epoxides under Mild Conditions
Herein, we report an efficient isomerization-transfer hydrogenation reaction sequence based on a cobalt pincer catalyst (1 mol %), which allows the synthesis of a series of anti-Markovnikov alcohols from terminal and internal epoxides under mild reaction conditions (≤55 °C, 8 h) at low catalyst loading. The reaction proceeds by Lewis acid (3 mol % Er(OTf)3)-catalyzed epoxide isomerization and subsequent cobalt-catalyzed transfer hydrogenation using ammonia borane as the hydrogen source. The general applicability of this methodology is highlighted by the synthesis of 43 alcohols from epoxides. A variety of terminal (23 examples) and 1,2-disubstituted internal epoxides (14 examples) bearing different functional groups are converted to the desired anti-Markovnikov alcohols in excellent selectivity and yields of up to 98%. For selected examples, it is shown that the reaction can be performed on a preparative scale up to 50 mmol. Notably, the isomerization step proceeds via the most stable carbocation. Thus, the regiochemistry is controlled by stereoelectronic effects. As a result, in some cases, rearrangement of the carbon framework is observed when tri-and tetra-substituted epoxides (6 examples) are converted. A variety of functional groups are tolerated under the reaction conditions even though aldehydes and ketones are also reduced to the respective alcohols under the reaction conditions. Mechanistic studies and control experiments were used to investigate the role of the Lewis acid in the reaction. Besides acting as the catalyst for the epoxide isomerization, the Lewis acid was found to facilitate the dehydrogenation of the hydrogen donor, which enhances the rate of the transfer hydrogenation step. These experiments additionally indicate the direct transfer of hydrogen from the amine borane in the reduction step.
Liu, Xin,Longwitz, Lars,Spiegelberg, Brian,T?njes, Jan,Beweries, Torsten,Werner, Thomas
p. 13659 - 13667
(2020/11/30)

Method for preparing 4-tert-butylphenethyl alcohol
The invention discloses a method for preparing 4-tert-butylphenethyl alcohol. The method specifically comprises the following steps: reacting phenethyl alcohol with methyl chloroformate to generate methyl phenethyl carbonate; subjecting methyl phenylethyl
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(2020/05/02)

Ruthenium-Catalyzed Selective Hydrogenation of Epoxides to Secondary Alcohols
A ruthenium(II)-catalyzed highly selective Markovnikov hydrogenation of terminal epoxides to secondary alcohols is reported. Diverse substitutions on the aryl ring of styrene oxides are tolerated. Benzylic, glycidyl, and aliphatic epoxides as well as diepoxides also underwent facile hydrogenation to provide secondary alcohols with exclusive selectivity. Metal-ligand cooperation-mediated ruthenium trans-dihydride formation and its reaction involving oxygen and the less substituted terminal carbon of the epoxide is envisaged for the origin of the observed selectivity.
Thiyagarajan, Subramanian,Gunanathan, Chidambaram
supporting information
p. 9774 - 9778
(2019/12/02)

Visible-Light-Mediated Anti-Markovnikov Hydration of Olefins
Considering that stoichiometric borane and oxidant are required in the classical alkene anti-Markovnikov hydration process, it remains appealing to achieve the transformation in a catalytic protocol. Herein, a visible-light-mediated anti-Markovnikov addition of water to alkenes by using an organic photoredox catalyst in conjunction with a redox-active hydrogen atom donor was developed, which avoided the need for a transition-metal catalyst, stoichiometric borane, as well as oxidant. Both terminal and internal olefins are readily accommodated in this transformation to obtain corresponding primary and secondary alcohols in good yields with single regioselectivity. This procedure can be scaled up to gram scale with a 230 turnover number based on photocatalyst.
Hu, Xia,Zhang, Guoting,Bu, Faxiang,Lei, Aiwen
p. 1432 - 1437
(2017/08/09)

Markovnikov-Selective, Activator-Free Iron-Catalyzed Vinylarene Hydroboration
Two series of structurally related alkoxy-tethered NHC iron(II) complexes have been developed as catalysts for the regioselective hydroboration of alkenes. Significantly, Markonikov-selective alkene hydroboration with HBpin has been controllably achieved using an iron catalyst (11 examples, 35-90% isolated yield) with up to 37:1 branched:linear selectivity. anti-Markovnikov-selective alkene hydroboration was also achieved using HBcat and modification of the ligand backbone (6 examples, 44-71% yields). In both cases, ligand design has enabled activator-free low-oxidation-state iron catalysis.
Macnair, Alistair J.,Millet, Clément R. P.,Nichol, Gary S.,Ironmonger, Alan,Thomas, Stephen P.
p. 7217 - 7221
(2016/10/14)

Hydrogenation of Esters to Alcohols Catalyzed by Defined Manganese Pincer Complexes
The first manganese-catalyzed hydrogenation of esters to alcohols has been developed. The combination of Mn(CO)5Br with [HN(CH2CH2P(Et)2)2] leads to a mixture of cationic and neutral Mn PNP pincer complexes, which enable the reduction of various ester substrates, including aromatic and aliphatic esters as well as diesters and lactones. Notably, related pincer complexes with isopropyl or cyclohexyl substituents showed very low activity.
Elangovan, Saravanakumar,Garbe, Marcel,Jiao, Haijun,Spannenberg, Anke,Junge, Kathrin,Beller, Matthias
supporting information
p. 15364 - 15368
(2016/12/03)

A Phosphine-Catalyzed Novel Asymmetric [3+2] Cycloaddition of C,N-Cyclic Azomethine Imines with δ-Substituted Allenoates
Catalytic asymmetric [3+2] cycloadditions of C,N-cyclic azomethine imines with δ-substituted allenoates have been developed in the presence of (S)-Me-f-KetalPhos, affording functionalized tetrahydroquinoline frameworks in good yields with high diastereo- and good enantioselectivities under mild condition. The substrate scope has been also examined. This is the first time that δ-substituted allenoates have been applied as a δ,γ-C-C bond participated C 2 synthon in asymmetric synthesis. Another round: Catalytic asymmetric [3+2] cycloaddition of C,N-cyclic azomethine imines with δ-substituted allenoates have been developed in the presence of (S)-Me-f-KetalPhos, affording functionalized tetrahydroquinoline frameworks in good yields with high diastereo- and good enantioselectivities under mild conditions. This is the first example applying δ-substituted allenoates as C 2 synthons in asymmetric δ,γ-C-C bond formation.
Wang, De,Lei, Yu,Wei, Yin,Shi, Min
supporting information
p. 15325 - 15329
(2016/02/18)

Oxidative degradation of fragrant aldehydes. Autoxidation by molecular oxygen
The oxidative degradation of fragrant aldehydes by molecular oxygen has been investigated. The oxygen consumption was monitored and the bond dissociation energy (BDE) of the aldehyde C(O)-H bond were calculated by DFT method. The oxidation products were identified by GC/MS. The different pathways accounting for the oxidative degradation are discussed. The main product is the acid, beside the formate ester. Both oxidation products result from the Baeyer-Villiger reaction involving a peracid R(CO)OOH whereas minor products arise from the hydroperoxide ROOH intermediate derived either from the acyl peroxy radical, R(CO)OO or from the decarboxylation of the peracid RC(O)OOH.
Marteau,Ruyffelaere,Aubry,Penverne,Favier,Nardello-Rataj
p. 2268 - 2275
(2013/04/10)

Iron-catalyzed reduction of carboxylic esters to alcohols
A novel catalytic system formed from Fe(stearate)2/NH 2CH2CH2NH2 and polymethylhydrosiloxane was directly developed for the hydrosilylation of carboxylic acid esters to alcohols. The catalytic method exhibits broad substrate scope, including 20 aliphatic, aromatic, and heterocyclic esters. The corresponding alcohols are obtained in moderate to very good yields. The first iron-catalyzed hydrosilylation of carboxylic acid esters to alcohols is described. A catalytic system formed by Fe(stearate)2/NH 2CH2CH2NH2 and polymethylhydrosiloxane (PMHS) is used for this transformation, which has a broad substrate scope, including 20 aliphatic, aromatic, and heterocyclic esters. The corresponding alcohols are obtained in moderate to very good yields. Copyright
Junge, Kathrin,Wendt, Bianca,Zhou, Shaolin,Beller, Matthias
p. 2061 - 2065
(2013/05/09)

Fe-promoted cross coupling of homobenzylic methyl ethers with Grignard reagents via sp3 C-O bond cleavage
The first iron-catalyzed formal cross coupling of homobenzylic methyl ethers with alkyl Grignard reagents is realized. The reaction is proposed to proceed through a sequence of dehydroalkoxylation to form the vinyl-intermediate, followed by Fe-catalyzed selective carbometalation to form a benzylic Grignard reagent.
Luo, Shuang,Yu, Da-Gang,Zhu, Ru-Yi,Wang, Xin,Wang, Lei,Shi, Zhang-Jie
supporting information
p. 7794 - 7796
(2013/09/02)

CATALYTIC ANTI-MARKOVNIKOV OXIDATION AND HYDRATION OF OLEFINS
The disclosure provides a dual-catalysis system for direct conversion of olefins to alcohols. The cooperative catalytic system contains one oxidizing catalyst and one transfer-hydrogenation catalyst. A wide variety of olefins, including aromatic and aliphatic olefins, can be used as the reactant. The transformation proceeds with anti-Markovnikov selectivity, and in some aspects provides primary alcohols as major products. The disclosure further provides a system for oxidation of olefins with anti-Markovnikov selectivity.
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(2012/07/14)

A new phenylalanine derivative acts as an antagonist at the AMPA Receptor GluA2 and introduces partial domain closure: Synthesis, resolution, pharmacology, and crystal structure
In order to map out molecular determinants for competitive blockade of AMPA receptor subtypes, a series of 2-carboxyethylphenylalanine derivatives has been synthesized and pharmacologically characterized in vitro. One compound in this series, (RS)-3h, showed micromolar affinity for GluA1o and GluA2(R)o receptors with an approximately 4-fold preference for GluA1/2 vs GluA3/4. In TEVC electrophysiological experiments (RS)-3h competitively antagonized GluA2(Q)i receptors. The X-ray structure of the active enantiomer (S)-3h in complex with GluA2-S1S2J showed a domain closure around 8°. Even though the nitro and the carboxyethyl groups of (S)-3h were both anchored to Tyr702 through a water H-bond network, these interactions only induced weak subtype selectivity. In spite of the fact that (S)-3h induced a domain closure close to that observed for partial agonists, it did not produce agonist responses at GluA2 receptors under nondesensitizing conditions. 2-Carboxyethylphenylalanine derivatives provide a new synthetic scaffold for the introduction of substituents that could lead to AMPA receptor subtype-selective ligands.
Szymańska, Ewa,Frydenvang, Karla,Contreras-Sanz, Alberto,Pickering, Darryl S.,Frola, Elena,Serafimoska, Zorica,Nielsen, Birgitte,Kastrup, Jette S.,Johansen, Tommy N.
supporting information; experimental part
p. 7289 - 7298
(2011/12/04)

Primary alcohols from terminal olefins: Formal anti-Markovnikov hydration via triple relay catalysis
Alcohol synthesis is critical to the chemical and pharmaceutical industries. The addition of water across olefins to form primary alcohols (anti-Markovnikov olefin hydration) would be a broadly useful reaction but has largely proven elusive; an indirect hydroboration/oxidation sequence requiring stoichiometric borane and oxidant is currently the most practical methodology. Here, we report a more direct approach with the use of a triple relay catalysis system that couples palladium-catalyzed oxidation, acid-catalyzed hydrolysis, and ruthenium-catalyzed reduction cycles. Aryl-substituted terminal olefins are converted to primary alcohols by net reaction with water in good yield and excellent regioselectivity.
Dong, Guangbin,Teo, Peili,Wickens, Zachary K.,Grubbs, Robert H.
scheme or table
p. 1609 - 1612
(2012/02/01)

An improved bouveault-blanc ester reduction with stabilized alkali metals
Significantly improved Bouveault-Blanc conditions for ester reduction have been developed using sodium in silica gel (Na-SG), a free-flowing powder that can be easily handled in the open atmosphere. Primary alcohols were prepared in excellent yield from a variety of aliphatic esters under mild reaction conditions. The chemistry presented here is far safer than the classic Bouveault-Blanc reduction and is competitive with more modern hydride reduction methods.
Bodnar, Brian S.,Vogt, Paul F.
supporting information; experimental part
p. 2598 - 2600
(2009/08/07)

Design and synthesis of phenethyl benzo[1,4]oxazine-3-ones as potent inhibitors of PI3Kinaseγ
The Type 1 PI3Kinases comprise a family of enzymes, which primarily phosphorylate PIP2 to give the second messenger PIP3, a key player in many intracellular signaling processes [Science, 2002, 296, 1655; Trends Pharmacol. Sci. 2003, 24, 366]. Of the four type 1 PI3Ks, the γ-isoform, which is expressed almost exclusively in leukocytes [Curr. Biol., 1997, 7, R470], is of particular interest with respect to its role in inflammatory diseases such as rheumatoid arthritis (RA) and chronic obstructive pulmonary disease (COPD) [Mol. Med. Today, 2000, 6, 347]. Investigation of a series of 4,6-disubstituted-4H-benzo[1,4]oxazin-3-ones has led to the identification of single-digit nanomolar inhibitors of PI3Kγ, several of which had good cell based activity and were shown to be active in vivo in an aspectic peritonitis model of inflammatory cell migration.
Lanni Jr., Thomas B.,Greene, Keri L.,Kolz, Christine N.,Para, Kimberly S.,Visnick, Melean,Mobley, James L.,Dudley, David T.,Baginski, Theodore J.,Liimatta, Marya B.
p. 756 - 760
(2007/10/03)

[1,2]-Wittig rearrangement from chloromethyl ethers
The reaction of different chloromethyl ethers 1 with an excess of lithium powder and a catalytic amount of 4,4′-di-tert-butylbiphenyl (2.5 mol %) in THF at 0 °C leads to the corresponding α-lithiomethyl ether intermediates, through a chlorine-lithium exchange, which spontaneously undergo a clean [1,2]-Wittig rearrangement affording the expected homobenzylic alcohols 2. This is the first version of this rearrangement starting from easily available chloromethyl ethers.
Gómez, Cecilia,Maciá, Beatriz,Lillo, Victor J.,Yus, Miguel
p. 9832 - 9839
(2007/10/03)

Structure-activity relationships of simplified resiniferatoxin analogues with potent VR1 agonism elucidates an active conformation of RTX for VR1 binding
We previously described a series of N-(3-acyloxy-2-benzylpropyl) homovanillate and N′-(4-hydroxy-3-methoxybenzyl) thiourea derivatives that were potent VR1 agonists with high-affinities and excellent analgesic profiles. The design of these simplified RTX analogues was based on our RTX-derived pharmacophore model which incorporates the 4-hydroxy-3- methoxyphenyl (A-region), C20-ester (B-region), orthophenyl (C1-region) and C3-keto (C2-region) groups of RTX. For the purpose of optimizing the spatial arrangement of the four principal pharmacophores on the lead agonists (1-4), we have modified the distances in the parent C-region, 3-acyloxy-2-benzylpropyl groups, by lengthening or shortening one carbon to vary the distances between the pharmacophores. We find that two of the amides, 4 and 19, possess EC50 values i) and calcium influx (EC50) values. The binding affinities of the agonists correlated best with the RMS values derived from RTX conformation E (r2=0.92), predicting a model of the active conformation of RTX and related vanilloids for binding to VR1. Poorer correlation was obtained between any of the conformations and the EC 50 values for calcium influx.
Lee, Jeewoo,Kim, Su Yeon,Park, Soyoung,Lim, Ju-Ok,Kim, Ji-Min,Kang, Myungshim,Lee, Jiyoun,Kang, Sang-Uk,Choi, Hyun-Kyung,Jin, Mi-Kyung,Welter, Jacqueline D.,Szabo, Tamas,Tran, Richard,Pearce, Larry V.,Toth, Attila,Blumberg, Peter M.
p. 1055 - 1069
(2007/10/03)

Non-imidazole histamine H3 ligands. Part I. Synthesis of 2-(1-piperazinyl)- and 2-(hexahydro-1H-1,4-diazepin-1-yl)benzothiazole derivatives as H3-antagonists with H1 blocking activities
New 2-(1-Piperazinyl)- and 2-(hexahydro-1H-1,4-diazepin-1-yl)benzothiazoles were prepared and tested as H1- and H3-receptor antagonists. A number of compounds showed weak H1-antagonistic activity, with pA2 values ranging from 5.5 to 6.1. The simple alkyl substituted, 2-[1-(4-methyl and 4-ethyl)piperazinyl] analogues show increasing, moderate H3-antagonistic activity (pA2=6.0, and pA2=7.0). The compounds with 4-phenylalkyl substitution, for both the piperazinyl and the hexahydro-1H-1,4-diazepin-1-yl homologues series, regardless of the different physicochemical properties of the para substituents at the phenyl ring, showed weak H3-antagonistic activity with pA2 values ranging from 4.4 to 5.6. Copyright (C) 1999 Elsevier Science S.A.
Walczynski, Krzysztof,Guryn, Roman,Zuiderveld, Obbe P.,Timmerman, Henk
p. 684 - 694
(2007/10/03)

Complexes of ketodiesters and related compounds with TiCl4. Attempts to use chelation to promote the simultaneous coordination of ketones by two Lewis acids
Carbonyl oxygen atoms have two formal lone pairs of electrons. In principle, both can be used simultaneously to form complexes with two or more Lewis acids. This multiple coordination promises to have a variety of interesting consequences; unfortunately,
Saied,Bachand,Wuest
p. 490 - 497
(2007/10/03)

Insecticidal quinazoline derivatives with (trifluoromethyl)diazirinyl and azido substituents as NADH:ubiquinone oxidoreductase inhibitors and candidate photoaffinity probes
Two candidate photoaffinity probes are designed from 4-substituted quinazolines known to be potent insecticides/acaricides and NADH:ubiquinone oxidoreductase inhibitors acting at or near the rotenone site. 4-(11- Azidoundecyl-2-amino)quinazoline, based on the undecylamino analog SAN 548A as a prototype, was synthesized in 18% overall yield from ethyl 10- undecenoate by oxidation of the terminal double bond, reductive amination, coupling to 4-chloroquinazoline, and functional group manipulation of the terminal ethyl ester to an alcohol, a mesylate and finally nucleophilic displacement with azide ions. 4-(4-(3-(Trifluoromethyl)-3H-diazirin-3- yl)phenethoxy)quinazoline [the (trifluoromethyl)diazirinyl analog of fenazaquin insecticide/acaricide] was prepared from 4-bromophenethyl alcohol in 31% overall yield by first introducing the trifluoromethylketone moiety followed by its conversion to the (trifluoromethyl)-diazirine and finally coupling to 4-chloroquinazoline as above. Both candidate photoaffinity probes have the inhibitory potency of rotenone (IC50 of 3-4 nM in each case). The azidoundecylamino compound has inadequate photoreactivity whereas that of the (trifluoromethyl)diazirinyl analog is ideal at 350 nm. Radiosynthesis of the latter photoaffinity ligand included introduction of the diazirinyl moiety as the carbene precursor, oxidation of (trifluoromethyl)diazirinylphenethyl alcohol to the corresponding acid with Jones' reagent, and reduction of the phenacetyl chloride intermediate with sodium borotritide to incorporate tritium.
Latli, Bachir,Wood, Edgardo,Casida, John E.
p. 445 - 450
(2007/10/03)

Optional ortho or alpha hydroxymethylation of alkylarenes
Treatment of arenes carrying methyl or primary alkyl groups in tetrahydrofuran solution with potassium tert-butoxide activated butyllithium followed by reaction with formaldehyde gives 2-arylalkanols.In contrast, if prior to the addition of the electrophile a stoichiometric amount of magnesium dibromide is added then the regioisomeric 2-alkylbenzyl alcohols are formed.
Guggisberg, Yves,Faigl, Ferenc,Schlosser, Manfred
p. 1 - 6
(2007/10/02)