Tag: M.W=150-200

Hopf, Henning published the artcileSterically hindered double bond systems. 2. On the preparation of highly substituted 1,3-dienes, Recommanded Product: 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, the publication is Chemische Berichte (1991), 124(9), 2075-84, database is CAplus.

Highly alkylated 1,3-dienes were prepared in good yield by treatment of 2-butyne-1,4-diol derivatives with organocuprates. Thus, the 2,3-dialkylated butadienes (Me₂C:CR)₂ (R = Me₃C, Me₂CH, Et, Me) are obtained by treating diacetate AcOCMe₂CCCMe₂OAc with two equivalent of the cuprates prepared from the Grignard reagents RMgX with CuBr/LiBr. The procedure may be extended to the synthesis of unsym. substituted 1,3-dienes by either treating the appropriate diacetates with two equivalent of the same cuprate as exemplified by the conversion of AcOCMe₂CCCH₂OAc into Me₂C:CRCR:CH₂ (R = Me₃C, Me₂CH) or by employing a stepwise approach in which only one reactive acetate leaving group is available for the cuprate reagent at any given time, thus allowing the change of the organometallic reagent in the course of the synthesis [preparation of the dienes Me₂C:CR²CR¹:CH₂ (R¹, R² = Me₃C, Me₂CH; Me₂CH, Me₃C) from the monoacetates AcOCMe₂CCCH₂OTHP (THP = tetrahydropyranyl)]. Mechanisms of these reactions are discussed.

Chemische Berichte published new progress about 27943-46-0. 27943-46-0 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Alkynyl,Ether, name is 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, and the molecular formula is C10H16O2, Recommanded Product: 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Johnson, C. David published the artcileProdrugs based on masked lactones. Cyclization of γ-hydroxy amides, Name: 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, the publication is Journal of Organic Chemistry (1988), 53(21), 5130-9, database is CAplus.

A versatile approach to prodrug design based on the lactonization of γ-hydroxy carbonyl compounds is investigated. A range of γ-hydroxy amides, e.g., RR¹C(OH)CH:CHCONHR²R³ [R = R¹ = H, Me; RR¹ = (CH₂)₅; R² = H, R³ = 4-C₆H₄Br; R² = Me, R³ = Ph], I and II (R⁴ = H, 4-Br, 4-OMe, 4-Me, 3-Cl) were prepared as models for amide-linked prodrugs. The rates of lactonization of these compounds were measured, and the effects of pH, leaving group pK_a, buffer species, and ionic strength were investigated. The kinetic data are consistent with changes in the rate-determining step with the nature of the buffer and with pH over the range 6-10. Some compounds show only small changes in rate over the pH range 7-9. The best model prodrugs studied have rates of amine expulsion that would probably be adequate for therapeutic use, but precise rates of drug liberation in vivo cannot be predicted from these data due to the problems of estimating the magnitude of biol. buffer catalysis and effects due to tissue binding. However, drug liberation half-lives in vivo in the region of 1 h for aromatic amides, less for aliphatic amides, may be achieved by using prodrugs that yield 4,4-dialkyl (or spiroalkyl)-(Z)-but-2-enoic acid lactones during drug release.

Journal of Organic Chemistry published new progress about 27943-46-0. 27943-46-0 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Alkynyl,Ether, name is 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, and the molecular formula is C10H16O2, Name: 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Lippincott, Daniel J. published the artcileSynthesis of Functionalized [3], [4], [5] and [6]Dendralenes through Palladium-Catalyzed Cross-Couplings of Substituted Allenoates, Synthetic Route of 27943-46-0, the publication is Angewandte Chemie, International Edition (2017), 56(3), 847-850, database is CAplus and MEDLINE.

A mild method for the synthesis of highly functionalized [3]-[6]dendralenes is reported, representing a general strategy to diversely substituted higher homologues of the dendralenes. The methodol. utilizes allenoates bearing various substitution patterns, along with a wide range of boron and alkenyl nucleophiles that couple under palladium catalysis leading to sp-, sp²-, and sp³-substituted arrays. Regioselective transformations of the newly formed unsym. dendralene derivatives are demonstrated. The use of micellar catalysis, where water is the global reaction medium, and room temperature reaction conditions, highlights the green nature of this technol.

Angewandte Chemie, International Edition published new progress about 27943-46-0. 27943-46-0 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Alkynyl,Ether, name is 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, and the molecular formula is C10H16O2, Synthetic Route of 27943-46-0.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Le, Anh published the artcileSelectivity between an Alder-ene reaction and a [2+2] cycloaddition in the intramolecular reactions of allene-tethered arynes, Recommanded Product: 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, the publication is Organic Chemistry Frontiers (2021), 8(13), 3390-3397, database is CAplus.

Substituent-dependent reactivity and selectivity in the intramol. reactions of arynes tethered with an allene were described. With a 1,3-disubstituted allene moiety, an Alder-ene reaction of an allenic C-H bond was preferred over a [2+2] cycloaddition, whereas a [2+2] cycloaddition of the terminal π-bond of the allene was preferred with a 1,1-disubstituted allene. With a 1,1,3-trisubstituted allene-tethered aryne, an Alder-ene reaction with an allylic C-H bond was preferred over a [2+2] cycloaddition

Organic Chemistry Frontiers published new progress about 27943-46-0. 27943-46-0 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Alkynyl,Ether, name is 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, and the molecular formula is C10H16O2, Recommanded Product: 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Eshon, Josephine published the artcileRegioselective Rh-Catalyzed Hydroformylation of 1,1,3-Trisubstituted Allenes Using BisDiazaPhos Ligand, Product Details of C10H16O2, the publication is Journal of Organic Chemistry (2017), 82(18), 9270-9278, database is CAplus and MEDLINE.

The efficient hydroformylation of 1,1,3-trisubstituted allenes is accomplished with low loadings of a Rh catalyst supported by a BisDiazaPhos (BDP) ligand. The ligand identity is key to achieving high regioselectivity, while the mild reaction conditions minimize competing isomerization and hydrogenation to produce β,γ-unsaturated aldehydes and their derivatives in excellent yields.

Journal of Organic Chemistry published new progress about 27943-46-0. 27943-46-0 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Alkynyl,Ether, name is 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, and the molecular formula is C10H16O2, Product Details of C10H16O2.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Fuerst, Andor published the artcileNew syntheses of 1α,25-dihydroxycholesterol, Computed Properties of 27943-46-0, the publication is Helvetica Chimica Acta (1982), 65(5), 1499-521, database is CAplus.

1α,25-Dihydroxycholesterol was prepared via 5 convergent syntheses by combining C₂₁– or C₂₂-steroids with C₄– or C₅-side-chain building blocks. Thus, pregnene I (R = tetrahydro-2-pyranyl, R¹ = CH₂O₃SC₆H₄Me-H) was combined with the dioxolane II, PhSO₂CH₂CH₂CMe₂OR² (R² = tetrahydro-2-pyranyl) and HCCCMe₂OR² and I (R = Ac, R¹ = CHO) was combined with Ph₃P:CHCH₂CMe₂OH. Also, pregnenone III was condensed with phosphorane IV.

Helvetica Chimica Acta published new progress about 27943-46-0. 27943-46-0 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Alkynyl,Ether, name is 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, and the molecular formula is C10H16O2, Computed Properties of 27943-46-0.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Kihira, Kenji published the artcileComparative biological studies of bile alcohols. IV. New bile alcohols. Synthesis of (22R)- and (22S)-5β-cholestane-3α,7α,12α,22,25-pentols, Application of 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, the publication is Steroids (1976), 27(3), 383-93, database is CAplus and MEDLINE.

Bisnorcholanal I, prepared from triacetylcholic acid by successive oxidative-decarboxylation, alk. hydrolysis, treatment with H2O2, alk. hydrolysis, and oxidation with Pb(OAc)4, was treated with 3-methyl-3-(tetrahydropyran-2-yloxy)butynylmagnesium bromide. Hydrogenation over PtO2 of the epimeric acetylenes followed by acid hydrolysis gave (22R)- and (22S)-cholestanepentols II. (22R)-II was identical with the metabolite of 5β-cholestane-3α,7α,25-triol formed in the rabbit.

Steroids published new progress about 27943-46-0. 27943-46-0 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Alkynyl,Ether, name is 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, and the molecular formula is C10H16O2, Application of 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Hoffmann, H. M. R. published the artcileThe intramolecular enyne Diels-Alder reaction. Stereoselective construction of tricyclic dioxa dienones and mechanistic outline, HPLC of Formula: 27943-46-0, the publication is Tetrahedron (1993), 49(40), 8999-9018, database is CAplus.

4-Methylpent-4-en-2-yn-1-ols and 6-hydroxy-2,3-dihydro-6H-pyran-3-ones are condensed in different ways to give a series of tricyclic dioxa dienones I [R = H, Me; R¹ = R² = H, Me, Et; R¹R² = (CH₂)₄, (CH₂)₅; R¹ = H, R² = Me, Ph, 2-thienyl, 3-thienyl] which contain the basic framework of the cadlinolides. A mechanism for the intramol. enyne-ene cycloisomerization and the origin of the resulting dienes is proposed.

Tetrahedron published new progress about 27943-46-0. 27943-46-0 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Alkynyl,Ether, name is 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, and the molecular formula is C10H16O2, HPLC of Formula: 27943-46-0.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Baggiolini, Enrico G. published the artcileStereocontrolled total synthesis of 1α,25-dihydroxycholecalciferol and 1α,25-dihydroxyergocalciferol, Category: tetrahydropyran, the publication is Journal of Organic Chemistry (1986), 51(16), 3098-108, database is CAplus.

1α,25-Dihydroxycholecalciferol and 1α,25-dihydroxyergocalciferol, the hormonally active forms of vitamin D₃ and vitamin D₂, were prepd by Horner-Wittig reaction of the phosphine oxide I [R = CH₂P(O)Ph₂] (II) with ketones III and IV, resp. The synthon III was obtained via stereospecific opening of epoxide V with NaOAc in AcOH followed by oxidative degradation of the isopropenyl side chain and dehydration of the intermediate VI. Photoisomerization of the resulting (E)-I (R = CO₂Et) gave I (R = CO₂Et), which was converted to II. III was obtained from the known intermediate VII. The introduction of the 25-hydroxy side chain was achieved by reaction of the lithium derivative of HCCCMe₂OR¹ (R¹ = tetrahydropyranyl) with the tosylate of VII; subsequent hydrogenation, deblocking, and oxidation reactions gaave III. IV was prepared by a stereocontrolled route that involves as the key step the [3 + 2] dipolar cycloaddition of nitrone VII with Me₂C:CHCO₂Me to give a 1:1 mixture of isoxazolidines IX. Stereochem. control was achieved by taking advantage of the thermal reversibility of the cycloaddition, which allows the reequilibration of undersired IX. (23S, 24S)-IX was readily transformed to amine X by reduction, followed by elimination of the nitrogen function, and finally oxidation to IV.

Journal of Organic Chemistry published new progress about 27943-46-0. 27943-46-0 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Alkynyl,Ether, name is 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, and the molecular formula is C10H16O2, Category: tetrahydropyran.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Liu, Yangbin published the artcileEnantioselective construction of branched 1,3-dienyl substituted quaternary carbon stereocenters by asymmetric allenyl Claisen rearrangement, Synthetic Route of 27943-46-0, the publication is Chemical Communications (Cambridge, United Kingdom) (2016), 52(80), 11963-11966, database is CAplus and MEDLINE.

The availability of enantiomerically enriched 1,3-dienyl substituted quaternary stereocenters is highly valuable for the synthesis of complex natural compounds Despite great advances in the area of construction of alkenyl-substituted types, a general, practical catalytic system that works for enantioselective formation of 1,3-diene derivatives still remains to be developed. Herein, we disclose the first asym. Claisen rearrangement of allenyl vinyl ethers to access optically active β-ketoesters, containing branched 1,3-butadienyl substituted stereocenters. A variety of substrates bearing a range of useful functional groups were well tolerated, thus affording the corresponding products with excellent enantioselectivities (up to 99% ee) and high yields (up to 91%).

Chemical Communications (Cambridge, United Kingdom) published new progress about 27943-46-0. 27943-46-0 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Alkynyl,Ether, name is 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, and the molecular formula is C10H16O2, Synthetic Route of 27943-46-0.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics