Substituted Benzenes: The Gu Synthesis of Rhazinal

2015 ◽  
Author(s):  
Douglass F. Taber
Keyword(s):  
Aryl Halide ◽  
Indian Institute ◽  
University Of California ◽  
University Of Pennsylvania ◽  
Ru Catalyst ◽  
Cu Catalyst ◽  
Institute Of Technology ◽  
The University ◽  
University Of Manchester ◽  
Structure Of Matter

Sisir K. Mandal of Asian Paints R&T Centre, Mumbai used (Tetrahedron Lett. 2013, 54, 530) a Ru catalyst to couple 2 with an electron-rich arene 1 to give 3. Jun-ichi Yoshida of Kyoto University (J. Am. Chem. Soc. 2013, 135, 5000) and John F. Hartwig of the University of California, Berkeley (J. Am. Chem. Soc. 2013, 135, 8480) also reported direct amination protocols. Tommaso Marcelli of the Politecnico di Milano and Michael J. Ingleson of the University of Manchester effected (J. Am. Chem. Soc. 2013, 135, 474) the electrophilic borylation of the aniline 4 to give 5. The regioselectivity of Ir-catalyzed borylation (J. Am. Chem. Soc. 2013, 135, 7572; Org. Lett. 2013, 15, 140) is complementary to the electrophilic process. Professor Hartwig carried (Angew. Chem. Int. Ed. 2013, 52, 933) the borylated product from 6 onto Ni-mediated coupling to give the alkylated product 7. Weiping Su of the Fujian Institute of Research on the Structure of Matter devised (Org. Lett. 2013, 15, 1718) an intriguing Pd-mediated oxidative coupling of nitroethane 9 with 8 to give 10. The coupling is apparently not proceeding via nitroethylene. Peiming Gu of Ningxia University developed (Org. Lett. 2013, 15, 1124) an azide-based cleavage that converted the aldehyde 11 into the formamide 13. Zhong-Quan Liu of Lanzhou University showed (Tetrahedron Lett. 2013, 54, 3079) that an aromatic carboxylic acid 14 could be oxidatively decarboxylated to the chloride 15. Gérard Cahiez of the Université Paris 13 found (Adv. Synth. Catal. 2013, 355, 790) mild Cu-catalyzed conditions for the reductive decarboxylation of aromatic carboxylic acids, and Debabrata Maiti of the Indian Institute of Technology, Mumbai found (Chem. Commun. 2013, 49, 252) Pd-mediated conditions for the dehydroxymethylation of benzyl alcohols (neither illustrated). Pravin R. Likhar of the Indian Institute of Chemical Technology prepared (Adv. Synth. Catal. 2013, 355, 751) a Cu catalyst that effected Castro-Stephens coupling of 16 with 17 at room temperature. Arturo Orellana of York University (Chem. Commun. 2013, 49, 5420) and Patrick J. Walsh of the University of Pennsylvania (Org. Lett. 2013, 15, 2298) showed that a cyclopropanol 20 can couple with an aryl halide 19 to give 21.

Oxidation and Reduction

2013 ◽  
Author(s):  
Douglass F. Taber
Keyword(s):  
Aryl Halide ◽  
Direct Reduction ◽  
University Of California ◽  
Yale University ◽  
University Of Pittsburgh ◽  
Ru Catalyst ◽  
Efficient Reduction ◽  
Radical Reduction ◽  
The University ◽  
Mediated Reduction

Kiyotomi Kaneda of Osaka University devised (Angew. Chem. Int. Ed. 2010, 49, 5545) gold nanoparticles that efficiently deoxygenated an epoxide 1 to the alkene 2. Robert G. Bergman of the University of California, Berkeley, and Jonathan A. Ellman, now of Yale University, reported (J. Am. Chem. Soc. 2010, 132, 11408) a related protocol for deoxygenating 1,2-diols. Dennis A. Dougherty of Caltech established (Org. Lett. 2010, 12, 3990) that an acid chloride 3 could be reduced to the phosphonate 4. Pei-Qiang Huang of Xiamen University effected (Synlett 2010, 1829) reduction of an amide 5 by activation with Tf2O followed by reduction with NaBH4. André B. Charette of the Université de Montreal described (J. Am. Chem. Soc. 2010, 132, 12817) parallel results with Tf2O/Et3SiH. David Milstein of the Weizmann Institute of Science devised (J. Am. Chem. Soc. 2010, 132, 16756) a Ru catalyst for the alternative reduction of an amide 7 to the amine 8 and the alcohol 9. Shi-Kai Tian of the University of Science and Technology of China effected (Chem. Commun. 2010, 46, 6180) reduction of a benzylic sulfonamide 10 to the hydrocarbon 11. Thirty years ago, S. Yamamura of Nagoya University reported (Chem. Commun. 1967, 1049) the efficient reduction of a ketone to the corresponding methylene with Zn/HCl. Hirokazu Arimoto of Tohoku University established (Tetrahedron Lett. 2010, 51, 4534) that a modified Zn/TMSCl protocol could be used following ozonolysis to effect conversion of an alkene 12 to the methylene 13. José Barluenga and Carlos Valdés of the Universidad de Oviedo effected (Angew. Chem. Int. Ed. 2010, 49, 4993) reduction of a ketone to the ether 16 by way of the tosylhydrazone 14. Kyoko Nozaki and Makoto Yamashita of the University of Tokyo and Dennis P. Curran of the University of Pittsburgh found (J. Am. Chem. Soc. 2010, 132, 11449) that the hydride 18 (actually a complex dimer) could effect the direct reduction of a halide 17 and also function as the hydrogen atom donor for free radical reduction and as the hydride donor for the Pd-mediated reduction of an aryl halide.

Functional Group Oxidation and Reduction

2015 ◽  
Author(s):  
Douglass F. Taber
Keyword(s):  
Direct Conversion ◽  
University Of Mississippi ◽  
Ru Catalyst ◽  
Mo Catalyst ◽  
University Of Arizona ◽  
Institute Of Technology ◽  
Diastereoselective Reduction ◽  
The University ◽  
University Of Manchester ◽  
Mediated Reduction

Debabrata Maiti of the Indian Institute of Technology Bombay found (Chem. Commun. 2012, 48, 4253) that the relatively inexpensive Pd(OAc)2 effectively catalyzed the decarbonylation of an aldehyde 1 to the hydrocarbon 2. Hui Lou of Zhejiang University used (Adv. Synth. Catal. 2011, 353, 2577) a Mo catalyst to effect reduction of the ester 3 to the hydrocarbon 4, with retention of all the skeletal carbons. Jon T. Njardarson of the University of Arizona showed (Chem. Commun. 2012, 48, 7844) that the allylic ether 5 could be reduced with high regioselectivity to give 6. José Barluenga and Carlos Valdés of the Universidad de Oviedo effected (Angew. Chem. Int. Ed. 2012, 51, 5950) the direct conversion of a ketone 7 to the azide 8. Although no cyclic ketones were included in the examples, there is a good chance that this will be the long-sought diastereoselective reduction of a cyclohexanone to the equatorial amine. Hideo Nagashima of Kyushu University reduced (Chem. Lett. 2012, 41, 229) the acid 9 directly to the aldehyde 1 using a ruthenium catalyst with the bis silane 10. Georgii I. Nikonov of Brock University described (Adv. Synth. Catal. 2012, 354, 607) a similar Ru-mediated silane reduction of an acid chloride to the aldehyde. Professor Nagashima used (Angew. Chem. Int. Ed. 2012, 51, 5363) his same Ru catalyst to reduce the ester 11 to the protected amine 12. Shmaryahu Hoz of Bar-Ilan University used (J. Org. Chem. 2012, 77, 4029) photostimulation to promote the SmI2-mediated reduction of a nitrile 13 to the amine 14. Bakthan Singaram of the University of California, Santa Cruz effected (J. Org. Chem. 2012, 77, 221) the same transformation with InCl3/NaBH4. David J. Procter of the University of Manchester described (J. Org. Chem. 2012, 77, 3049) what promises to be a general method for activating Sm metal to form SmI2. Mark T. Hamann of the University of Mississippi directly reduced (J. Org. Chem. 2012, 77, 4578) the nitro group of 15 to the alkylated amine 16. Cleanly oxidizing aromatic methyl groups to the level of the aldehyde without overoxidation has been a challenge.

scholarly journals Meet the APSA Council and Officers

2012 ◽  
Vol 45 (01) ◽  
pp. 151-154
Keyword(s):  
Harvard University ◽  
University Of California ◽  
Massachusetts Institute ◽  
University Of Southern California ◽  
Massachusetts Institute Of Technology ◽  
New Members ◽  
Reed College ◽  
Institute Of Technology ◽  
The University ◽  
University Of Manchester

As noted in the October issue ofPS, G. Bingham Powell, Jr., the Marie E .and Joseph C. Wilson Professor of Political Science at the University of Rochester, became APSA's 108th president on September 4, 2011, at the close of the APSA Annual Meeting. Eight new members of the APSA council were elected fall 2011. The new members are Paul Gronke, Reed College; Ange-Marie Hancock, University of Southern California; David A. Lake, University of California, San Diego; Taeku Lee, University of California, Berkeley; Kenneth J. Meier, Texas A&M University; Kathleen Thelen, Massachusetts Institute of Technology; Stephen M. Walt, Harvard University; and Angelia R. Wilson, University of Manchester.

Organic Functional Group Interconversion

2017 ◽  
Author(s):  
Douglass F. Taber
Keyword(s):  
New Orleans ◽  
Indian Institute ◽  
Unsaturated Aldehyde ◽  
Terminal Alkyne ◽  
Vinyl Ethers ◽  
Water Conditions ◽  
Cu Catalyst ◽  
Institute Of Technology ◽  
The University ◽  
Hydrolysis Of

Gojko Lalic of the University of Washington developed (Angew. Chem. Int. Ed. 2014, 53, 6473) conditions for the preparation of the fluoride 2 by SN2 displacement of the triflate 1. Ross M. Denton of the University of Nottingham showed (Tetrahedron Lett. 2014, 55, 799) that a polymer-bound phosphine oxide activated with oxalyl bromide would convert an alcohol 3 to the bromide 4. The polymer could be filtered off and reactivated directly. Jonas C. Peters and Gregory C. Fu of Caltech devised (J. Am. Chem. Soc. 2014, 136, 2162) a photochemically-activated Cu catalyst that mediated the displacement of the bromide 5 by the amide 6 to give 7. Mark L. Trudell of the University of New Orleans used (Synthesis 2014, 46, 230) an Ir catalyst to couple the amide 9 with the alcohol 8, leading to 10. Tohru Fukuyama of Nagoya University converted (Org. Lett. 2014, 16, 727) the unsaturated aldehyde 11 into the ester 12. As the transformation proceeded via proton­ation of the enolized acyl cyanide, the less stable diastereomer was formed kinetically. Brindaban C. Ranu of the Indian Association for the Cultivation of Science developed (Org. Lett. 2014, 16, 1040) conditions for the coupling of an alkenyl halide 13 with a phenol, leading to the vinyl ether 14. Inter alia, this would be a convenient way to hydrolyze an alkenyl halide to the aldehyde. Vinyl ethers can also be oxidized directly to the ester, and to the unsaturated aldehyde. Pallavi Sharma and John E. Moses of the University of Lincoln observed (Org. Lett. 2014, 16, 2158) that the cyanation of the alkenyl halide 15 delivered 16, with retention of the geometry of the alkene. Jitendra K. Bera of the Indian Institute of Technology Kanpur uncovered (Tetrahedron Lett. 2014, 55, 1444) “on water” conditions for the hydrolysis of a terminal alkyne 17 to the methyl ketone 18. Jiannan Xiang and Weimin He of Hunan University prepared (Eur. J. Org. Chem. 2014, 2668) the keto phosphonate 20 by hydrolysis of the alkynyl phosphonate 19. Ken-ichi Fujita of the National Institute of Advanced Industrial Science and Technology cyclized (Tetrahedron Lett. 2014, 55, 3013) the alkyne 21 with CO₂, leading to 22.

Enantioselective Synthesis of Alcohols and Amines: The Ichikawa Synthesis of (+)-Geranyllinaloisocyanide

2015 ◽  
Author(s):  
Douglass F. Taber
Keyword(s):  
Allylic Alcohol ◽  
Florida State University ◽  
State University ◽  
Quaternary Amine ◽  
National University ◽  
Cu Catalyst ◽  
Enantioselective Addition ◽  
Institute Of Technology ◽  
The University ◽  
University Of Manchester

Shuichi Nakamura of the Nagoya Institute of Technology reduced (Angew. Chem. Int. Ed. 2011, 50, 2249) the α-oxo ester 1 to 2 with high ee. Günter Helmchen of the Universität-Heidelberg optimized (J. Am. Chem. Soc. 2011, 133, 2072) the Ir*-catalyzed rearrangement of 3 to the allylic alcohol 4. D. Tyler McQuade of Florida State University effected (J. Am. Chem. Soc. 2011, 133, 2410) the enantioselective allylic substitution of 5 to give the secondary allyl boronate, which was then oxidized to 6. Kazuaki Kudo of the University of Tokyo developed (Org. Lett. 2011, 13, 3498) the tandem oxidation of the aldehyde 7 to the α-alkoxy acid 8. Takashi Ooi of Nagoya University prepared (Synlett 2011, 1265) the secondary amine 10 by the enantioselective addition of an aniline to the nitroalkene 9. Yixin Lu of the National University of Singapore assembled (Org. Lett. 2011, 13, 2638) the α-quaternary amine 13 by the addition of the aldehyde 11 to the azodicarboxylate 10. Chan-Mo Yu of Sungkyunkwan University added (Chem. Commun. 2011, 47, 3811) the enantiomerically pure 2-borylbutadiene 15 to the aldehyde 14 to give 16 in high ee. Because the allene is readily dragged out to the terminal alkyne, this is also a protocol for the enantioselective homopropargylation of an aldehyde. Lin Pu of the University of Virginia devised (Angew. Chem. Int. Ed. 2011, 50, 2368) a protocol for the enantioselective addition of 17 to the aldehyde 18 to give 19. Xiaoming Feng of Sichuan University developed (Angew. Chem. Int. Ed. 2011, 50, 2573) a Mg catalyst for the enantioselective addition of 21 to the α-oxo ester 20. Tomonori Misaka and Takashi Sugimura of the University of Hyogo added (J. Am. Chem. Soc. 2011, 133, 5695) 23 to 24 to give the Z-amide 25 in high ee. Marc L. Snapper and Amir H. Hoveyda of Boston College developed (J. Am. Chem. Soc. 2011, 133, 3332) a Cu catalyst for the enantioselective allylation of the imine 26. Jonathan Clayden of the University of Manchester effected (Org. Lett. 2010, 12, 5442) the enantioselective rearrangement of the amide 29 to the α-quaternary amine 30.

Preparation of Benzene Derivatives

2011 ◽  
Author(s):  
Douglass Taber
Keyword(s):  
Aryl Halide ◽  
Allylic Alcohol ◽  
Chemical Technology ◽  
University Of Pennsylvania ◽  
Benzene Derivatives ◽  
Aryl Iodide ◽  
University Of Illinois ◽  
Institute Of Technology ◽  
The University ◽  
Optimized Conditions

Several new methods have been put forward for the functionalization of benzene derivatives. J. S. Yadav of the Indian Institute of Chemical Technology, Hyderabad has devised (Chem. Lett. 2008, 37, 652) a procedure for direct thiocyanation, converting 1 into 2. Sukbok Chang of KAIST has established (Chem. Commun. 2008, 3052) that both NH4Cl and aqueous NH3 could be used to directly aminate an aryl iodide such as 3. John F. Hartwig of the University of Illinois has developed (J. Am. Chem. Soc. 2008, 130, 7534) a protocol for the directed borylation of anilines such as 5 and of phenols, based on a transient silylation. Karsten Menzel of Merck West Point (Tetrahedron Lett. 2008, 49, 415) has observed selective exchange of tribromobenzene derivatives such as 7, with the direction of the selectivity being controlled by the fourth substituent on the benzene. Gary A. Molander of the University of Pennsylvania has extensively developed the stable, readily prepared trifluoroborates, exemplified by 10 (J. Org. Chem. 2008, 73, 2052) and 14 (Organic Lett. 2008, 10, 1795) as partners for Suzuki-Miyaura coupling. The conversion of 9 to 10 is complementary to aminocarbonylation, exemplified by the conversion of 12 to 13 reported (Tetrahedron Lett. 2008, 49, 2221) by Bhalchandra M. Bhanage of the Institute of Chemical Technology, University of Mumbai. The coupling of 9 with 14 is complementary to the long-known Heck coupling of an aryl halide such as 16 with an allylic alcohol, as illustrated by the preparation of 18 described (Tetrahedron Lett. 2008, 49, 3279) by Martin E. Maier of the Universität Tübingen. Professor Hartwig has also (Organic Lett. 2008, 10, 1545, 1549) optimized conditions for the Pd-catalyzed arylation of ester enolates such as 19. Gang Zhou of Schering-Plough, Kenilworth, NJ has developed (Organic Lett. 2008, 10, 2517) a related transformation, the arylation of deprotonated sulfonamides. Peter Somfai of the Royal Institute of Technology, Stockholm has established (Angew. Chem. Int. Ed. 2008, 47, 1907) a complementary procedure, base-mediated elimination of t -butoxide from 24, followed by 1,2-addition of an aryl or heteroaryl Grignard reagent.

Voices After Disaster

2021 ◽  
Author(s):  
Roger Few ◽  
Mythili Madhavan ◽  
Narayanan N.C. ◽  
Kaniska Singh ◽  
Hazel Marsh ◽  
...  
Keyword(s):  
Indian Institute ◽  
Community Members ◽  
Policy And Practice ◽  
Group Discussions ◽  
East Anglia ◽  
Other Information ◽  
The Media ◽  
Institute Of Technology ◽  
The University ◽  
Disaster Narratives

This document is an output from the “Voices After Disaster: narratives and representation following the Kerala floods of August 2018” project supported by the University of East Anglia (UEA)’s GCRF QR funds. The project is carried out by researchers at UEA, the Indian Institute for Human Settlements (IIHS), the Indian Institute of Technology (IIT), Bombay, and Canalpy, Kerala. In this briefing, we provide an overview of some of the emerging narratives of recovery in Kerala and discuss their significance for post-disaster recovery policy and practice. A key part of the work was a review of reported recovery activities by government and NGOs, as well as accounts and reports of the disaster and subsequent activities in the media and other information sources. This was complemented by fieldwork on the ground in two districts, in which the teams conducted a total of 105 interviews and group discussions with a range of community members and other local stakeholders. We worked in Alleppey district, in the low-lying Kuttanad region, where extreme accumulation of floodwaters had been far in excess of the normal seasonal levels, and in Wayanad district, in the Western Ghats, where there had been a concentration of severe flash floods and landslides.

Using Mammon for Righteousness

2017 ◽  
Author(s):  
Joan Marie Johnson
Keyword(s):  
University Of California ◽  
Massachusetts Institute ◽  
Massachusetts Institute Of Technology ◽  
Access To Education ◽  
Intellectual Achievement ◽  
Institute Of Technology ◽  
The University

Chapter 5 explores what happened when women approached existing coeducational schools offering restricted gifts to benefit women. These donations either forced a school to open its doors to women or increased the number of women admitted by providing scholarships for women or erecting a women’s building or a women’s dormitory. Like the college founders, these donors believed that women were capable of the same intellectual achievement as men but found that many of America’s best universities resisted coeducation. The women in this chapter, including Mary Garrett, and Phoebe Hearst and the gifts they gave show how money could be wielded to force changes that would benefit women, in the form of access to education and professions formerly restricted to men. Moreover, coeducation at these schools, including Johns Hopkins, Massachusetts Institute of Technology, and the University of California, Berkeley, was especially significant. If women were welcomed at these important institutions, they could demonstrate their intellectual and professional capabilities and equality with men.

Practical Enantioselective Construction of Arrays of Stereogenic Centers: The Jørgensen Synthesis of the Autoregulator IM-2

2011 ◽  
Author(s):  
Douglass Taber
Keyword(s):  
University Of Pennsylvania ◽  
Gel Chromatography ◽  
Max Planck ◽  
West Virginia University ◽  
Clemson University ◽  
Stereogenic Centers ◽  
Cu Catalyst ◽  
Enantioselective Epoxidation ◽  
Silica Gel Chromatography ◽  
The University

Armando Córdova of Stockholm University found (Angew. Chem. Int. Ed. 2008, 47, 8468) that the enantiomerically-enriched diastereomers from aminosulfenylation of 1 were readily separable by silica gel chromatography. Benjamin List of the Max-Planck-Institut, Mülheim developed (Angew. Chem. Int. Ed. 2008, 47, 8112) what appears to be a general protocol for the enantioselective epoxidation of enones such as 4. Paolo Melchiorre of the Università di Bologna devised (Angew. Chem. Int. Ed. 2008, 47 , 8703) a related protocol for the enantioselective aziridination of enones. Xue-Long Hue of the Shanghai Institute of Organic Chemistry and Yun-Dong Wu of the Hong Kong University of Science and Technology optimized (J. Am. Chem. Soc. 2008, 130 , 14362) a Cu catalyst for enantioselective Mannich homologation of imines such as 6. Guofu Zhong of Nanyang Technological University, Singapore established (Angew. Chem. Int. Ed. 2008, 47, 10187; Organic Lett. 2008 , 10 , 4585) that enantioselective α-aminoxylation of an ω-alkenyl aldehyde such as 9 could lead to defined arrays of stereogenic centers. George A. O’Doherty of West Virginia University devised (Organic Lett. 2008, 10, 3149) a protocol for the enantioselective hydration of 12 to 13 . René Peters, now at the University of Stuttgart, designed (Angew. Chem. Int. Ed. 2008, 47, 5461) an Al catalyst for the enantioselective combination of an acyl bromide 15 with an aldehyde 14 to deliver the β–lactone 16. Hajime Ito and Masaya Sawamura of Hokkaido University established (J. Am. Chem. Soc. 2008, 130, 15774) that the allenyl borane from 17 added to aldehydes such as 18 with high ee. Keiji Maruoka of Kyoto University developed (Tetrahedron Lett. 2008, 49, 5369) an organocatalyst for the Mannich homologation of an aldehyde such as 20 to 21. R. Karl Dieter of Clemson University showed (Organic Lett. 2008, 10, 2087) that 23, readily prepared in high ee, could be displaced sequentially with two different Grignard reagents, to give 24. Jeffrey W. Bode, now at the University of Pennsylvania, found (Organic Lett. 2008, 10, 3817) that bisulfite adducts such as 25 served well for the addition of unstable chloroaldehydes to 26 to give 27.

Metal-Mediated Carbocyclic Construction: The Simpkins Synthesis of Ialibinones A and B

2013 ◽  
Author(s):  
Douglass F. Taber
Keyword(s):  
Gold Catalyst ◽  
Conjugate Addition ◽  
South Florida ◽  
Pt Catalyst ◽  
General Strategy ◽  
Ru Catalyst ◽  
University Of Technology ◽  
Rh Catalyst ◽  
Institute Of Technology ◽  
The University

Adriaan J. Minnaard and Ben L. Feringa of the University of Groningen devised (J. Am. Chem. Soc. 2010, 132, 14349) what promises to be a general strategy for the construction of enantiomerically pure cyclopropanes, based on conjugate addition to acceptors such as 1 . X. Peter Zhang of the University of South Florida developed (J. Am. Chem. Soc. 2010, 132, 12796) a Co catalyst for the enantioselective cyclopropanation of α-olefins such as 3. Seiji Iwasa of Toyohashi University of Technology designed (Angew. Chem. Int. Ed. 2010, 49, 8439) a resin-bound Ru catalyst that could be used repeatedly for the enantioselective cyclization of the ester 6. Rai-Shung Lin of National Tsing-Hua University showed (Angew. Chem. Int. Ed. 2010, 49, 9891) that a gold catalyst could expand the alkyne 8 to the cyclobutene 9. Takao Ikariya of the Tokyo Institute of Technology reported (J. Am. Chem. Soc. 2010, 132, 16637) a detailed study of the enantioselective conjugate addition of malonate 11 to cyclopentenone 10. Vladimir A. D’yakonov of the Russian Academy of Sciences, Ufa, showed (Tetrahedron Lett. 2010, 51, 5886) that a cyclic alkyne 13 could be annulated to the cyclopentenone 14. Shunichi Hashimoto of Hokkaido University also designed (Angew. Chem. Int. Ed. 2010, 49, 6979) a resin-bound Rh catalyst that could also be used repeatedly for the enantioselective cyclization of the ester 15. Tushar Kanti Chakraborty of the Central Drug Research Institute used (Tetrahedron Lett. 2010, 51, 4425) Ti(III) to mediate the diastereoselective cyclization of 17 to 18. Alexandre Alexakis of the University of Geneva extended (Synlett 2010, 1694) enantioselective conjugate addition of isopropenyl to the more difficult enone 19. Joseph P. A. Harrity of the University of Sheffield showed (Org. Lett. 2010, 12, 4832) that Pd could catalyze the rearrangement of 21 to 22. Strategies for the controlled construction of polycyclic ring systems are also important. Günter Helmchen of the Universität Heidelberg showed (J. Org. Chem. 2010, 75, 7917) that 23 was efficiently cyclized to the diene with Pt catalyst. The reaction could be carried out in the presence of the dienophile 24 to give 25 directly.

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