322 research outputs found
Domino Heck–Diels–Alder Reactions of Monosubstituted Bicyclopropylidenes
No full textA three-component domino Heck-Diels-Alder reaction involving pinacol bicyclopropylideneboronate (8b), iodobenzene (9) and methyl acrylate (12) under Jeffery conditions [Pd(OAc)(2), PPh(3), K(2)CO(3), Et(4)NCl, MeCN] produced a mixture of phenylspiro[2.5]octeneboronates syn/anti-(E)-14b and methyl phenylspirooctenecarboxylate 25 in 25 and 38 % yield, respectively. The major product 25 was most probably formed via the homoallylpalladium complex 23b undergoing deboropalladation rather than dehydropalladation. Similarly, reactions of tributylstannyl- and hydroxydimethylsilyl-substituted bicyclopropylidenes 8c-d with 9 and tert-butyl acrylate gave the tert-butyl phenylspirooctenecarboxylate 26 via the diene 24 formed by demetallopalladation processes. The reaction of methyl 1,1'-bicyclopropylidene-2-carboxylate (8e) with iodobenzene (9) in the presence of tert-butyl acrylate (13) furnished a mixture of regimsomeric and diastereomeric spirooctenes syn/anti-(E)-15e and syn/anti-(Z)-15e in 69 and 6 % yield, respectively. The structures of the major pair of diastereomers syn-(E)-15e and anti-(E)-15e were rigorously proved by X-ray crystal structure analyses
Cyclopropyl Building Blocks in Organic Synthesis. Part 143. A Two‐Step, Three‐Component Queuing Cascade Leading to Dihydrobenzoxepine and Dihydrobenzazepine Derivatives.
No full textA palladium-catalyzed reaction of methylenespiropentane (11) with iodobenzene (12) under typical Heck conditions [Pd(OAC)(2), PPh3, Et3N, DMF] produced a mixture of the unstable [3]dendralene 13 and allylidenecyclopropane 14 in 38 % yield. When an analogous reaction with iodobenzene was carried out in the presence of morpholine (25) and of tris(2-furyl)phosphane (TFP) instead of triphenylphosphane, the dienes 26, 28 and 31 were generated by nucleophilic trapping of pi-allylpalladium intermediates 30 and 32. The cross coupling of methylenespiropentane (11) with the functionalized aryl iodides 33a-g in the presence of a palladium precatalyst [Pd(OAc)2, TFP, Et3N, DMF] at 80 degrees C, 3 h, provided the seven-membered 3,4-dimethylene-substituted heterocycles 34a-g and 35b which, upon addition of dimethyl fumarate (19), underwent Diels-Alder reactions to furnish bicyclic and higher oligocyclic dihydrobenzoxepine and -benzazepine derivatives 36a-g and 37b, yet in rather moderate yields of 18-29 % only. The overall process constitutes a one-pot, two-step, three-component queuing cascade.
Cyclopropyl Building Blocks for Organic Synthesis. Part 138. Diels—Alder Reactions of Novel (1′‐Arylallylidene)cyclopropanes with Heterodienophiles.
No full textRedesign Terminal Terpadu Pinang Baris
No full textThe project chosen by the author is a terminal facility which is located at Pinang
Baris Terminal. The Pinang Baris Terminal serves public transport vehicles with a
route west to the Nanggroe Aceh Darussalam (NAD) Region. The problems found
were unified vehicle circulation, less strategic departure and arrival areas, and a lack
of a number of standard facilities not found at the Pinang Baris Bus Terminal, such
as the absence of a health post, bus maintenance and washing areas and the absence
of barriers between vehicle traffic and passengers. Other facilities required by the
regulations are available, although not all of them function properly, many of the
facilities are damaged or unused, such as waiting rooms which are rarely used by
passengers while waiting for the bus. On this project which is the scope of the design
consists of designing the terminal in accordance with the regulations, laws and
provisions of the Government, redesigning the Pinang Baris Terminal according to
the predetermined land area, and expanding the terminal. In designing this project,
the authors apply and follow the laws and regulations regarding terminals in design,
so that the Pinang Baris Integrated Terminal can become a terminal that complies
with terminal standards. With this application to the project, it is hoped that the author
will be able to produce design solutions that can provide comfort for users and make
the Pinang Baris Integrated Terminal a standard-compliant terminal108 HalamanSkripsi Sarjan
Diels-Alder reactions of novel (1 '-arylallylidene)cyclopropanes with heterodienophiles
No full textPalladium-catalyzed cross-coupling of various aryl iodides with bicyclopropylidene provided isolable (1'arylallylidene)cyclopropanes, which reacted with a number of carbonyl compounds in the presence of Eu(fod)(3) under high pressure to furnish oxaspiro[2.5]octene derivatives in moderate to good yields (22-69%). The reactions of the allylidenecyclopropanes with two azo compounds as dienophiles afforded diazaspiro[2.5]octenes in high yields (82 and 99%) even at ambient pressure. When treated with nitrosobenzene, two of the allylidenecyclopro-panes gave the Diels-Alder adducts in up to 83 and 40% yield. 2,5-Diiodo-pxylene coupled twice with bicyclopropylidene, and the product underwent a twofold Diels-Alder reaction with nitrosobenzene to produce the bis(spirocyclopropaneoxazine) derivative in 88% yield. This overall transformation can be brought about in a one-pot, two-step operation by addition of the nitrosoarene to the reaction mixture immediately after formation of the allylidenecyclopropanes to furnish various 5-oxa-4-azaspiro[2.5]oct-7-ene derivatives in 22-77% yield. The coupling of methyl bicyclopropylidenecarboxylate with 2,6-dimethylphenyl iodide produced a mixture of very stable regioisomeric allylidenecyclopropane derivatives in 90% yield. The reaction of this mixture with N-phenyl-triazolinedione gave a corresponding mixture of the spirocyclopropanated heterobicycles in 61% yield
Palladium‐Catalyzed Cross‐Coupling Reactions and Electrocyclizations—Efficient Combinations for New Cascade Reactions.
No full textRecommended from our members
First record of the genus Baris Germar, 1817 (Coleoptera: Curculionidae), in Dominican amber
No full textA new weevil species – Baris grossacavis Poinar
and Legalov, sp. nov. (Coleoptera: Curculionidae) – is described
from Dominican amber. The new species is close to
Baris rubripes Casey, 1892, but differs by possessing large
punctures over much of its body, including the pronotum;
elytral intervals with rows of narrow scales, and narrow elytral
intervals.
The fossil is the first record of the subfamily Baridinae
from any amber source and the first record from the Miocene.This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Copernicus Publications on behalf of the Museum für Naturkunde Berlin. The published article can be found at: www.fossil-record.net/home.html
Evaluasi Karakteristik Parkir Bus Tipe A Di Terminal Pinang Baris sebagai Terminal Bus Tipe A
No full textThis study was conducted to determine how the condition Pinang Baris Terminal currently associated with the characteristics of parking. This study uses a field survey by direct observation in Terminal Pinang Baris by spreading surveyor at certain points in order to facilitate the recording of data in order to obtain a valid observation. Direct observation is done by manually recording the arrival time data and exit the bus, license plate number, and the name of the bus company. Research analysis using Microsoft Exel. Results of identification and field research has been on the analysis shows a maximum level of parking characteristics in Pinang Baris Terminal and it is known that there are three issues that must be resolved. First, the buildup of bus parking AKDP manifold small and MPU bus that we can see on the pictures and the documentation of the calculation in the Parking Index. Secondly, the vehicle bus parking AKDP which do not in place and this can be seen in the image documentation. Third, when the AKAP bus will maneuver to get into the parking lot AKAP bus, it takes quite a long time and could hinder other transport to pass. In this thesis, the author has provided solutions to three problems are found, because it must be found a solution that does not affect the operational performance in the future Pinang Baris Terminal
Enflasyon Hedefleyen Gelismekte Olan Ulkelerin Kriz Donemindeki Faiz Kararlari
No full text[TR] Merkez bankalarinin politika tepkilerinin enflasyon disi degiskenlerle bagintili bir gorunum arz etmesi kuresel kriz doneminde dikkat ceken bir gelisme olmustur. Enflasyon hedeflemesi rejimini benimsemis gelismekte olan ulkeleri inceleyen bu calisma, faiz kararlari ile enflasyon disi unsurlar arasinda kriz doneminde olusan baga ragmen, geleneksel tepki fonksiyonu degiskenlerinin onemini korudugunu tespit etmektedir. [EN] During the global crisis, central banks’ policy reactions were somewhat associated with factors other than inflation. Focusing on inflation-targeting emerging market economies, this study documents that traditional variables are still important in explaining the monetary reaction functions of central banks, despite the emergence of a relationship between the policy rates and factors other than inflation during the crisis period.
Value Chains and WTO Disputes: Compliance at the dispute settlement mechanism
No full textAs economic populism and protectionism increasingly threatens the global trade order, this book examines the behavior of World Trade Organization (WTO) members at the judicial arm of the WTO—the dispute settlement mechanism (DSM). The author explores why and when governments cooperate at the WTO and comply with the ruling of its panels, focusing on how the growth of global value chains through the internationalization of trade and production has increased the importance of both trade liberalization and supra-national governance and policy-making. Finding that domestic organized interests—i.e. firms and sectors—mobilize and lobby national governments to change their domestic policies to better harmonize with their international trade commitments, the author outlines how the time it takes to comply with adverse WTO rulings is shorter when the potential domestic costs of non-compliance outweigh protectionist interests. The author’s innovative research design highlights the conditions under which the WTO can preserve the rules of international trade and support a more open, global economy
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