Abstract
Sequential addition of a C-nucleophile and a C-electrophile to enantiomerically pure
arene tricarbonyl chromium complexes 3a ,b, 6 , and 8b , containing aryl bound chiral oxazoline, SAMP-hydrazone and chiral imine auxiliaries
affording substituted cyclohexadienes. C-Nucleophiles included alkyl-, vinyl-, and
phenyl-lithium reagents. C-Electrophiles included methyl iodide, allyl bromide, benzyl
bromide, and propargyl bromides. The 1,3-cylohexadienes were obtained with a 1,5,6-substitution
pattern. The results are consistent with a diastereoselective exo -nucleophilic addition to an ortho position of the complexed arene, followed by addition of the electrophile to the
metal center. With allyl, ben-zyl, and propargyl groups, direct reductive elimination
then yielded trans-5,6-substituted products. With methyl iodide, reductive elimination
was preceded by CO insertion and acetyl cyclohexadienes were formed exclusively whose
in situ deprotonation/alkylation gave products in which three C-substituents had been
added across an arene double bond with complete regio- and stereocontrol. The two
path-ways reflect migratory aptitude to carbonylation. An X-ray structure determination
of the phenyl oxazoline complex 3a allowed a rationalization of observed diastereoselectivity. Asymmetric induction was
very high with the oxazoline and the SAMP-hydrazone complexes (>90% de) whereas the
chiral benzaldehyde imine complex 8b afforded the substituted diene aldehydes in moderate enantiomeric purity (34-58% ee).
Changing the reaction medium from THF to toluene in reactions with 8b resulted in products of the opposite chirality.
Key words
diastereoselective dearomatization - cyclohexadiene - arene Cr(CO)3 complexes - imine - oxazoline - SAMP-hydrazone
References
<A NAME="RM02601SS-1">1 </A>
Makosza M.
Russ. Chem. Bull.
1996,
45:
491
<A NAME="RM02601SS-2">2 </A>
Snieckus V.
Chem. Rev.
1990,
90:
879
3a </A>
Snieckus V.
Pure Appl. Chem.
1994,
66:
2155
3b </A>
Hartwig JF.
Synlett
1997,
329
3c </A>
Wolfe JP.
Wagaw S.
Marcoux JF.
Buchwald S.
L. Acc. Chem. Res.
1998,
31:
805
<A NAME="RM02601SS-4">4 </A>
Bach T.
Angew. Chem. Int. Ed. Engl.
1996,
35:
729
5a </A>
Semmelhack MF. In
Comprehensive Organometallic Chemistry II
Vol. 12:
Abel EW.
Stone FGA.
Wilkinson G.
Pergamon;
New-York:
1995.
p.979
5b </A>
Pape AR.
Kaliappan KP.
Kündig EP.
Chem Rev.
2000,
100:
2917
<A NAME="RM02601SS-6">6 </A>
Semmelhack MF.
Clark GR.
Farina R.
Saeman M.
J. Am. Chem. Soc.
1979,
101:
217
7a </A>
Pearson AJ.
Gontcharov AV.
Woodgate PD.
Tetrahedron Lett.
1996,
37:
3087
7b </A>
Pearson AJ.
Gontcharov AV.
J. Org. Chem.
1998,
63:
152
<A NAME="RM02601SS-8">8 </A>
Semmelhack MF.
Schmalz H.-G.
Tetrahedron Lett.
1996,
37:
3089
<A NAME="RM02601SS-9">9 </A>
Semmelhack MF.
Garcia JL.
Cortes D.
Farina R.
Hong R.
Carpenter BK.
Organometallics
1983,
2:
467
10a </A>
Kündig EP.
Amurrio D.
Liu RG.
Ripa A.
Synlett
1991,
657
10b </A>
Kündig EP.
Ripa A.
Liu R.
Amurrio D.
Bernardinelli G.
Organometallics
1993,
12:
3724
<A NAME="RM02601SS-11">11 </A> For approach 2, see :
Amurrio D.
Khan K.
Kündig EP.
J. Org. Chem.
1996,
61:
2258
<A NAME="RM02601SS-12">12 </A> For approach 3, see :
Kündig EP.
Quattropani A.
Inage M.
Ripa A.
Dupré C.
Cunningham JAF.
Bourdin B.
Pure Appl. Chem.
1996,
68:
97
13a </A>
Schmalz H.-G.
Schellhaas K.
Angew. Chem. Int. Ed. Engl.
1996,
35:
2146
13b </A>
Quattropani A.
Anderson G.
Bernardinelli G.
Kündig EP.
J. Am. Chem. Soc.
1997,
119:
4773
13c </A>
Schellhaas K.
Schmalz H.-G.
Bats JW.
Chem.- Eur. J.
1998,
4:
57
14a </A>
Kündig EP.
Ripa A.
Bernardinelli G.
Angew. Chem. Int. Ed. Engl.
1992,
31:
1071
14b </A>
Kündig EP.
Bernardinelli G.
Beruben D.
Crousse B.
Fretzen A.
Ratni H.
Schnell B.
Xu L.-H.
Electronic Conference on Heterocyclic Chemistry "98 (Keynote Article 015)
Rzepa HS.
Kappe O.
Imperial College Press;
London:
1998.
14c </A>
Kündig EP.
Amurrio D.
Anderson G.
Beruben D.
Khan K.
Ripa A.
Ronggang L.
Pure Appl. Chem.
1997,
543
15 </A>
Diastereoselective meta nucleophile addition/protonation reactions have been carried out with chiral Cr(CO)3 bound aryl ethers. See refs. 7 and 8.
<A NAME="RM02601SS-16">16 </A>
Fretzen A.
Ripa A.
Liu R.
Bernardinelli G.
Kündig EP.
Chem.- Eur. J.
1998,
4:
251
<A NAME="RM02601SS-17">17 </A>
Kündig EP.
Ripa A.
Liu RG.
Bernardinelli G.
J. Org. Chem.
1994,
59:
4773
<A NAME="RM02601SS-18">18 </A>
McKennon MJ.
Meyers AI.
Drauz K.
Schwarm M.
J. Org. Chem.
1993,
58:
3568
<A NAME="RM02601SS-19">19 </A>
Enders D.
Klatt M.
Encyclopedia of Reagents for Organic Reactions
Vol. 1:
Paquette LA.
John Wiley & Sons;
Chichester:
1995.
p.178
<A NAME="RM02601SS-20">20 </A>
Kündig EP.
Perret C.
Spichiger S.
Bernardinelli G.
J. Organomet. Chem.
1985,
286:
183-200
<A NAME="RM02601SS-21">21 </A>
Gant TG.
Meyers AI.
Tetrahedron
1994,
50:
2297
<A NAME="RM02601SS-22">22 </A>
In the absence of the Cr(CO)3 group, phenyl oxazolines react with n-BuLi to give products arising from ortho- arene lithiation. See ref 21.
<A NAME="RM02601SS-23">23 </A>
Jackman LM.
Scarmoutzos LM.
J. Am. Chem. Soc.
1984,
106:
4627
<A NAME="RM02601SS-24">24 </A>
Kündig EP.
Cunningham JAF.
Paglia P.
Simmons DP.
Bernardinelli G.
Helv. Chim. Acta
1990,
73:
386
<A NAME="RM02601SS-25">25 </A>
Crystal structure determination of 3a : Cr(CO)3 (C12 H15 NO), Mr = 325.3; µ = 0.782 mm-1 , dx = 1.451 g.cm-3 , monoclinic, P 21, Z = 4, a = 11.0923(10), b = 11.2412(7), c = 12.0144(12)Å, β = 96.471(11)°, V =
1488.5(2)Å3 , yellow prism 0.10 x 0.20 x 0.26. Cell dimensions and intensities were measured at
200 K on a Stoe IPDS diffractometer with graphite-monochromated Mo Kα radiation (λ
= 0.71069 Å). 22868 measured reflections, 7125 unique reflections of which 3728 were
observables (|Fo| > 4 σ (Fo)); Rint for equivalent reflections 0.069. Data were corrected
for absorption (T min, max = 0.8492, 0.9441). Full-matrix least-squares refinement
based on F using weight of 1/[σ2 (Fo)+ 0.0003(Fo)2 ] gave final values R = 0.032, w R2 = 0.032 and Flack parameter x = 0.02(5). Hydrogen atoms were placed in calculated
positions.
<A NAME="RM02601SS-26">26 </A>
Crystallographic data (excluding structure factors) have been deposited to the Cambridge Crystallographic Data Base (deposition No. CCDC163963, CCDC163964 for 3a and 6 respectively). Copies of the data can be obtained free of charge on application to
the CCDC, 12 Union Road, Cambridge CB2 1EZ, UK (fax: Int. + 44(1223)336-033; e-mail:
deposit@ccdc.cam.ac.uk).
27a </A>
Sammakia T.
Latham HA.
Schaad DR.
J. Org. Chem.
1995,
60:
10
27b </A>
Nishibayashi Y.
Uemura S.
Synlett
1995,
79
27c </A>
Zhang W.
Adachi Y.
Hirao T.
Ikeda I.
Tetrahedron Asymmetr.
1996,
7:
451
<A NAME="RM02601SS-28">28 </A>
Fretzen A.
Kündig EP.
Helv. Chim. Acta
1997,
80:
2023
<A NAME="RM02601SS-29">29 </A>
Crystal structure determination of 6 : Cr(CO)3 (C13 H18 N2 O), Mr = 354.3; µ = 0.689 mm-1 , dx = 1.415 g.cm-3 , monoclinic, P 21, Z = 4, a = 10.229(2), b = 13.276(2), c = 12.267(3)Å, β = 92.973(6)°, V = 1663.6(6)Å3 , yellow prism 0.11 0.24 0.24. Cell dimensions and intensities were measured at
room temperature on a Philips PW1100 diffractometer with graphite-monochromated Mo
Kα]radiation (λ = 0.71069 Å). Two reference reflections measured every 60 min showed
variation of about 10%; all intensities were corrected for this drift. -10 < h <10;
0 < k < 14; 0 < l < 12 and all anti-reflections; 4522 measured reflections, 4194 unique
reflections of which 3155 were observables (|Fo| > 4 σ (Fo)); Rint for equivalent
reflections 0.031. Data were corrected for absorption (T min, max = 0.8814, 0.9245).
Full-matrix least-squares refinement based on F using weight of 1/[σ2 (Fo)+ 0.0003(Fo)2 ] gave final values R = 0.050, w R2 = 0.047 and Flack parameter x = 0.02(6). Hydrogen atoms were placed in calculated
positions. The methoxymethyl substituant of the anti-conformer is disordered. Two
disordered fragments have been refined with population parameters of 0.70 and 0.30
for C12b-O1b-C13b and C12b’-O1b’-C13b’ respectively. The partial decomposition of
the crystal during data collection and the presence of the disorder, led to relatively
large uncertainties in the final coordinates.
<A NAME="RM02601SS-30">30 </A>
Pache S.
Botuha C.
Franz R.
Kündig EP.
Einhorn J.
Helv. Chim Acta
2000,
83:
2436
<A NAME="RM02601SS-31">31 </A>
Shriver DF.
Drezdon MA.
The Manipulation of Air-Sensitive Compounds , 2nd ed.
John Wiley & Sons;
New York:
1986.
<A NAME="RM02601SS-32">32 </A>
Still CW.
Kahn M.
Mitra A.
J. Org. Chem.
1978,
43:
2923
<A NAME="RM02601SS-33">33 </A>
Gilman H.
Cartledge FK.
J. Organomet. Chem.
1964,
2:
682
<A NAME="RM02601SS-34">34 </A>
Rawson DJ.
Meyers AI.
J. Org.Chem.
1991,
56:
2292
35a </A>
Giardina D.
Marrazzo A.
Marucci G.
Piloni MG.
Quaglia W.
Il Farmaco
1991,
46:
861
35b </A>
Kinbara K.
Sakai K.
Hashimoto Y.
Saigo K.
Tetrahedron: Asymmetry
1996,
7:
1539
36a </A>
Wu M.-J.
Pridgen LN.
J. Org. Chem.
1991,
56:
1340
36b </A>
Pridgen LN.
Mokhallalati MK.
Wu M.-J.
J. Org. Chem.
1992,
57:
1237
36c </A>
Higashiyama K.
Inoue H.
Takahashi H.
Tetrahedron Lett.
1992,
33:
235
36d </A>
Bernardinelli G.
Fernandez D.
Gosmini R.
Meier P.
Ripa A.
Schüpfer P.
Treptow B.
Kündig EP.
Chirality
2000,
12:
529
37a </A>
Desobry V.
Kündig EP.
Helv. Chim. Acta
1981,
64:
1288
37b </A>
Hudecek M.
Gadja V.
Toma S.
J. Organomet. Chem.
1991,
413:
155
37c </A>
Morley JA.
Woolsey NF.
J. Org. Chem.
1992,
57:
6487
<A NAME="RM02601SS-38">38 </A>
Davies SG.
Goodfellow CL.
J. Chem. Soc., Perkin Trans. 1
1990,
393
<A NAME="RM02601SS-39">39 </A> See for example:
Perrin DD.
Armarego WLF.
Purification of Laboratory Chemicals
Pergamon Press;
Oxford:
1988.
3rd Ed.
<A NAME="RM02601SS-40">40 </A> For a review on recovery of carbonyl compounds from N ,N -dialkyl hydrazones see:
Enders D.
Wortmann L.
Peters R.
Acc. Chem. Res.
2000,
33:
157
