Transition Metal-Catalyzed 1,2-Diamination of Alkenes. Group Meeting Timothy Chang

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Transition Metal-Catalyzed 1,2-Diamination of Alkenes Group Meeting Timothy Chang 04-27-10

Valuable 1,2-Diamine Motif H H S Biotin CH H H Pt Eloxatin (Anticaner) H 2 AcH CHEt 2 Tamiflu (Antiviral) Et Ph H Cl C 2 H Lorabid (Antibacterial) Ph Me Ph Me Cl Py Ru Cl Py Ph Ph Ph P Cl Ru P Ph Ph Cl H H Ph Ph Mn Cl Metathesis Catalyst (Grubbs) Hydrogenation Catalyst (oyori) Epoxidation Catalyst (Jacobsen) For a review on various synthetic methods of vicinal diamines, see Lucet, D.; Gall, T. L.; Mioskowski, C. Angew. Chem. Int. Ed. 1998, 37,2580. For a review on the transition-metal catalyzed diamination, see Cardona, F.; Goti A. ature Chemistry 2009, 1, 269.

smium Mediated Diamination s 4 + Ph 3 P 2equiv CH 2 Cl 2 reflux,48h s 63% C 2 Et s + Et 2 C 1.5 equiv DCM rt,5h s 84% C 2 Et C 2 Et recovered unchanged from preparativeglcat250 o C - Cis-disubstituted olefins react sluggishly. - Different amounts of hydroxyaminated products were observed for other olefins such as styrene and 1-decene. Chong, A..; shima, K. Sharpless, K. B. 1977J. Am. Chem. Soc. 99, 3420. For a review on osmium mediated diamination, see Muñiz, K. ew J. Chem.2005, 29, 1371.

Palladium Mediated Diamination PdCl 2 (PhC) 2 2equv THF,0 o C,5min Me 2 H (9 equiv) -40 o C 45min mcpba (10 equiv) 15min thenrt,3h 1.KBH 4 2. ah H 2 H 2 77% (based on Pd) Proposed Mechanism: Me 2 H Ph D PdCl Me 2 Me 2 2 (PhC) Me 2 D 2 H [] Me 2 D H Me 2 H H H D Ph [Pd II ] H Ph H Ph [Pd IV ] Bäckvall, J.-E. C. Tet. Lett. 1978, 19, 163.

Palladium Catalyzed xidative Intramolecular Diamination H R Conditions () H n R R R () n Conditions: A:Pd(Ac) 2 (5mol%),PhI(Ac) 2 (2.2equiv),Me 4 Cl/aAc(1equiv),CH 2 Cl 2,RT,12h. B:Pd(Ac) 2 (25mol%),PhI(Ac) 2 (2.2equiv),CH 2 Cl 2,RT,48h. C:Pd(Ac) 2 (10mol%),PhI(Ac) 2 (2.2equiv),CH 2 Cl 2,RT,12h. Tos Tos Tos Tos Me Me Me R=Me,92%(A) R=Ph,95%(A) 91%(A) 94%(A) Streuff, J.; Hövelmann, C. H.; ieger, M.; Muñiz, K. J. Am. Chem. Soc. 2005, 127,14586. 86%(B) 89%(C) -Base is required (generated in situ from Me 4 Cl/aAc) for reactivity (A). -o reactivity difference by using Me 4 Ac. - Chlorinated intermediate may not be involved. Tos - Sulfamide substrates gave aminoacetoxylated product. 95%(A) PhI(Ac) 2 (2equiv) Tos

The verall Stereochemistry of Diamination The acetoxy intermediate is not involved. Conditions: Pd(Ac) 2 (5 mol%) PhI(Ac) 2 (2 equiv) Me 4 Cl/aAc (1 equiv) CH 2 Cl 2, RT, 12 h Anti diamination Which step involves the inversion of the configuration? Anti diamination Streuff, J.; Hövelmann, C. H.; ieger, M.; Muñiz, K. J. Am. Chem. Soc. 2008, 130,763.

Stereochemistry of Aminopalladation and Titration Experiment ot isolable 1b Syn aminopalladationdue to geometric constraint of the urea. Streuff, J.; Hövelmann, C. H.; ieger, M.; Muñiz, K. J. Am. Chem. Soc. 2008, 130,763.

Stereochemistry of Aminopalladation and Titration Experiment ot isolable Streuff, J.; Hövelmann, C. H.; ieger, M.; Muñiz, K. J. Am. Chem. Soc. 2008, 130,763.

Modes of Syn Aminopalladation Streuff, J.; Hövelmann, C. H.; ieger, M.; Muñiz, K. J. Am. Chem. Soc. 2008, 130,763.

Rate Determining Step X H H Tos Aminopalladation is the RDS. X=H,,Cl,Br,F,C Pd(Ac) 2 (5mol%) PhI(Ac) 2 (2equiv) Me 4 Cl/aAc(1equiv) CH 2 Cl 2,RT,3h X Tos EDG EWG Streuff, J.; Hövelmann, C. H.; ieger, M.; Muñiz, K. J. Am. Chem. Soc. 2008, 130,763.

Proposed Mechanism for the Second C- Bond Formation Conditions: Pd(Ac) 2 (5 mol%), PhI(Ac) 2 (2 equiv), Me 4 Cl/aAc (1 equiv), CH 2 Cl 2, RT, 2 h 2 2 4 2 2 The second C- bond formation is not the RDS. Ion pair Electrophilicity of -CH 2 -[Pd IV ] + is enhanced S 2 type reductive elimination Streuff, J.; Hövelmann, C. H.; ieger, M.; Muñiz, K. J. Am. Chem. Soc. 2008, 130,763.

Proposed Catalytic Cycle Streuff, J.; Hövelmann, C. H.; ieger, M.; Muñiz, K. J. Am. Chem. Soc. 2008, 130,763.

An Example of Syn Diamination Conditions: Pd(Ac) 2 (10 mol%), PhI(Ac) 2 (1.4 equiv), Me 4 Cl/aAc (1.1 equiv), DMF, RT, 14 h Syn diamination R = Tol 89% yield Muñiz, K. J. Am. Chem. Soc. 2007, 129,14542.

ickel-catalyzed Diamination Using Sulfamide Terminal alkenes are good substrates. Muñiz, K.; Streuff, J.; Hövelmann, C. H.; úñez, A. Angew. Chem. Int. Ed. 2007, 46,7125.

Pd-Catalyzed Diamination of Terminal Alkenes Using FBS Byproducts Me Me R H Me 4a Me Me R C()CF 3 5a Sibbald, P. A.; Michael, F. E. rg. Lett. 2009, 11,1147.

Sibbald, P. A.; Michael, F. E. rg. Lett. 2009, 11,1147. Proposed Catalytic Cycle

The verall Stereochemistry of Diamination Mechanistic implications of the two C- bond formations from the overall syn diamination: 1. Anti aminopalladation followed by S 2 displacement of the C-Pd bond. 2. Syn aminopalladation followed by C- reductive elimination (retentive). Sibbald, P. A.; RosewallC. F.; Swartz, R. D.; Michael, F. E. J. Am. Chem. Soc. 2009, 131, 15945.

Stereochemistry of the Aminopalladation(1 st C- Bond Formation) Chelation from the acetamide minimizes β-hydride elimination. Inversion is required for the 2 nd C- bond formation for the overall syn diamination. Sibbald, P. A.; RosewallC. F.; Swartz, R. D.; Michael, F. E. J. Am. Chem. Soc. 2009, 131, 15945.

Proposed Mechanism for the 2 nd C- Bond Formation Sibbald, P. A.; RosewallC. F.; Swartz, R. D.; Michael, F. E. J. Am. Chem. Soc. 2009, 131, 15945.

Challenges in the Palladium Catalyzed Alkene Diamination Challenges: 1. Catalyst poisoning 2. Protonation of amine source 2 3. xidation of amine source 2 4. β-hydride elimination (route I) 5. Activation of Pd-C bond for a second attack by amine 2 Bar, G. L. J.; Lloyd-Jones, G. C.; Booker-Milburn, K. l. J. Am. Chem. Soc. 2005, 127,7308.

Pd-Catalyzed Intermolecular 1,2-Diamination of Conjugated Dienes Bar, G. L. J.; Lloyd-Jones, G. C.; Booker-Milburn, K. l. J. Am. Chem. Soc. 2005, 127,7308.

Pd-Catalyzed Diamination of Conjugated Alkenes - Conjugated dienes are effective substrates. - Highly stereoselective and regioselective at the internal double bond. -Z isomers do not react. Du, H.; Zhao, B.; Shi, Y. J. Am. Chem. Soc. 2007, 129,762.

Synthesis of Di-tert-butyldiaziridinone Greene, F. D.; Stowell, J. C.; Bergmark, W. R. J. rg. Chem.1969, 34, 2254. Du, H.; Zhao, B.; Shi, Y. rg. Synth.2009, 86, 315.

Properties of Diaziridinones C= R R R R R cyclopropanones aziridinones diaziridinones 1813-1840 1837-1850 1855-1880 cm -1 C= ketones amides ureas (saturated, aliphatic) ~1710 1650-1690 1660-1695 cm -1 Br 1.325 Å, typical amides(~1.33 Å) Br Me Me Me Me 1.601 Å F 2 -F 2 (1.47Å) H 2 -H 2 (1.45Å) The angle between the -substituent and thediaziridinoneplaneis56 o. Greene et. al. JC1969, 34, 2254.; JC1978, 43, 922.; JC 1976412813. Heine, H. W. The Chemistry of Heterocyclic Compounds; Hassner, A., Ed; John Wiley & Sons, Inc: ew York, 1983; pp 547.

Proposed Catalytic Cycle Pd(0) R R Pd Pd Pd R R Du, H.; Zhao, B.; Shi, Y. J. Am. Chem. Soc. 2007, 129,762.

Possible Reasons for High Stereoselectivity and Reactivity of E-Isomer

MR Study of the Stoichiometric Reaction 177.3 ( 13 C) 159.3 ( 13 C) 33.6 Ais consumed in 1 min when (E)-1-methoxybutadiene (6g) was added at 85 min. 58.1 19.8 ( 31 P) 1.36 ppm 1.32 ppm 59.3 27.2 1.59 ppm 1.05 ppm (0.04 mmol) Stoichiometric Reaction monitored by 1 H MR Zhao, B.; Du, H.; Cui, S.; Shi, Y. J. Am. Chem. Soc. 2010, 132,3523. Pd(PPh 3 ) 4 (0.03 mmol) 5(0.02 mmol) C 6 D 6, 40 o C A is a possible intermediate. xidative Addition is likely the RDS.

Kinetic Studies Me 6g E:Z=15.7:1 0.24mmolE + 5 0.2 mmol Pd(PPh 3 ) 4 (0.02mmol) C 6 D 6,40 o C Me 7g o induction period. PPh 3 dissociates rapidly. Quantitative conversion. o side reaction. Zhao, B.; Du, H.; Cui, S.; Shi, Y. J. Am. Chem. Soc. 2010, 132,3523. 1 st order in diaziridinone 5. 1 st order in Pd(PPh 3 ) 4 (not shown).

Kinetic Studies 6g(0.12 mmol Eisomer), 5(0.1 mmol), Pd(PPh 3 ) 4 (0.01 mmol) Zero-order in diene 6g. 6g(0.12 mmol Eisomer), 5(0.1 mmol), Pd(PPh 3 ) 4 (0.01 mmol) Inverse 1 st -order in PPh 3. Zhao, B.; Du, H.; Cui, S.; Shi, Y. J. Am. Chem. Soc. 2010, 132,3523.

Kinetic Studies R 6 + Pd Ph 3 P PPh 3 C 6 D 6,40 o C Me A 7 C- bond formation is slower for e-deficient dienes. -Acan be observed using 6iunder catalyticreaction conditions ([A]is independent of PPh 3 ). Zhao, B.; Du, H.; Cui, S.; Shi, Y. J. Am. Chem. Soc. 2010, 132,3523.

Refining the Catalytic Cycle 7-membered urea was not observed - Rational for high regioselectivity? - Why is cis-alkene unreactive? RDS for e-rich dienes. Details of insertion? Associative displacement? The olefin insertion into Pd- is slower for electron-deficient dienes. Zhao, B.; Du, H.; Cui, S.; Shi, Y. J. Am. Chem. Soc. 2010, 132,3523.

Catalytic Asymmetric Diamination of Conjugated Alkenes Du, H.; Yuan, W.; Zhao, B.; Shi, Y. J. Am. Chem. Soc. 2007, 129,11688.

Diamination at Allylic and Homoallylic Carbons R 2 R 2 R 2 Ph Et n-c 6 H 13 CH 2 Bn CH 2 n-c 6 H 13 R 1 + Yield(%) 90(7h) 68 74 90 78 Pd(PPh 3 ) 4 (10mol%) neat 65 o C,12h 2.75 equiv 55-93% yield R 2 slowaddition R 1 76% Ph Du, H.; Yuan, W.; Zhao, B.; Shi, Y. J. Am. Chem. Soc. 2007, 129,7496. Me - Highly stereoselective. 93% - o reactions for olefins with internal double bonds (e.g. trans-5-decane and cis-cyclooctene). Et 55% n-bu n-c 6 H 13 Me 64% Et 92% Ph

Bisdiamination A single diastereomer Using 5 mol% Pd(PPh 3 ) 4 : 10a (14%) and 10b (20%) were isolated after 12 h. 10a and 10b gave 11 under the diamination reaction condition. Du, H.; Yuan, W.; Zhao, B.; Shi, Y. J. Am. Chem. Soc. 2007, 129,7496.

Proposed Catalytic Cycles 2 equiv Du, H.; Yuan, W.; Zhao, B.; Shi, Y. J. Am. Chem. Soc. 2007, 129,7496.

Asymmetric Diamination at Allylic and Homoallylic Carbons R + 2.5 equiv slow addition Pd 2 (dba) 3 (5mol%) L*(22mol%) neat 65 o C,6h 50-85% yield 89-94% ee R Me Me P Me Me L* R Et n-c 5 H 11 CH 2 Ph i-pr Ph Yield(%) 50 71 67 51 80 ee(%) 90 91 93 94 90 80%(92%ee) n-c 6 H 13 85%(91%ee) Bn Me 67%(92%ee) n-c 5 H 11 81%(90%ee) n-c 5 H 11 Du, H.; Yuan, W.; Zhao, B.; Shi, Y. J. Am. Chem. Soc. 2007, 129,8590. 69%(89%ee) Me Me TMS TMS 70%(97:3 dr) 66%(94:6 dr) Ligand control overrides substrate control

Wang, B.; Du,.; Shi, Y. Angew. Chem. Int. Ed. 2008, 47,8224. Diamination using Thiadiaziridine

Preliminary Studies on Mechanism Diaminationmay may not proceed via a diene species Initial allylic amination is possible. o cyclization was observed without 4. Wang, B.; Du,.; Shi, Y. Angew. Chem. Int. Ed. 2008, 47,8224.

Wang, B.; Du,.; Shi, Y. Angew. Chem. Int. Ed. 2008, 47,8224. Proposed Catalytic Cycle

Cu(I)-Catalyzed Diamination of Conjugated Dienes (1) Yuan, W.; Du, H.; Zhao, B.; Shi, Y. rg. Lett. 2007, 9,2589.

Cu(I)-Catalyzed Diamination of Conjugated Dienes (2) Me Me + + 1.5 equiv 15equiv 1.5 CuCl(10 mol%) P(Ph) 3 (10mol%) C 6 D 6,rt,6h CuCl(10 mol%) P(Ph) 3 (10mol%) C 6 D 6,65 o C,6h Me Me + 1:1.3 65% Me 58% Ph + 1.5 equiv CuCl(10 mol%) P(Ph) 3 (10mol%) C 6 D 6,rt,6h Ph Z/E=3.3/1 76% Ph D D + 1.5 equiv Yuan, W.; Du, H.; Zhao, B.; Shi, Y. rg. Lett. 2007, 9,2589. CuCl(10 mol%) P(Ph) 3 (10mol%) C 6 D 6,rt,6h Ph D H D + Ph 65:35 73% D D H

Yuan, W.; Du, H.; Zhao, B.; Shi, Y. rg. Lett. 2007, 9,2589. Proposed Catalytic Cycle

Cu(I)-Catalyzed Asymmetric Diamination of Conjugated Dienes Du, H.; Zhao, B.; Yuan, W.; Shi, Y. rg. Lett. 2008, 10,4231.

Cu(I)-Catalyzed Diamination with ther itrogen Sources R + R=aryl heteroaryl alkyne alkylether S 1.2 equiv CuCl-P(n-Bu) 3 (10-20 mol%, 1:1) CDCl 3,rt-65 o C 7-48 h R S 45-91% yield - Electron-deficient olefin(ethyl acrylate) and aliphatic substituted olefin(1-octene) are not reactive. R + R=aryl heteroaryl alkyne alkene diene C CuCl-P(n-Bu) 3 C (10 mol%, 1:2) CDCl 3,50-65 o C 24h R 1.2 equiv 48-86% yield - o multiple diaminations with dienes or trienes. - Selective at the terminal olefin. - Electron-deficient olefin(ethyl acrylate) and aliphatic substituted olefin(1-octene) are not reactive. o reaction Ts Decomposed rapidly Zhao, B.; Yuan, W.; Du, H.; Shi, Y. rg. Lett. 2007, 9,4943. Du, H.; Zhao, B.; Shi, Y. rg. Lett. 2008, 10,1087.

Conclusions -Transition-metal catalyzed 1,2-diamination allows rapid access to protected diamines from alkenes. However, deprotection conditions are quite harsh (e.g. LAH, reflux con. HCl). - High catalyst loadings are often required. - Limited enantioselective approach available. -The dinitrogen source has a strong influence on the reaction at the terminal or the internal alkene. -Some mechanistic details are elucidated. More studies are required (e.g. nickel catalyzed and copper catalyzed diaminations). - Much work remained to be done to make this methodology general and practical.

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