Stereoselective Intermolecular Carbolithiation of Open-Chain and Cyclic 1-Aryl-1-alkenyl N,N-Diisopropylcarbamates Coupled with Electrophilic Substitution. Observation of p-Carboxylation in a Benzyllithium Derivative

Abstract

1-Aryl-1-alkenyl N,N-diisopropylcarbamates (1) are obtained from alkyl aryl ketones and N,N-diisopropylcarbamoyl chloride (CbCl) by heating with excess pyridine. These undergo facile syn-carbolithiation by alkyllithium/diamine and produce configurationally stable lithiated benzyl carbamates, which have been trapped with different electrophiles. If the reaction is carried out in the presence of chiral diamines, such as (-)-sparteine or (-)-α-isosparteine, moderate enantiofacial differentiation is observed.

1-alkenyl carbamates - benzyl carbamates - chiral benzyllithium compounds - carbolithiation - (-)-sparteine

References

<A NAME="RT10601SS-1A">1a</A> Ziegler K. Gellert HG. Liebigs Ann. Chem.  1950,  567:  195 

<A NAME="RT10601SS-1B">1b</A> Morton M. Anionic Polymerisation: Principles and Practice   Academic Press; New York: 1963. 

<A NAME="RT10601SS-2">2</A> Review: Marek I. J. Chem. Soc., Perkin Trans 1  1999,  535 

<A NAME="RT10601SS-3">3</A> Review on early work: Klumpp GW. Recl. Trev. Chim. Pay-Bas  1986,  105:  1 

<A NAME="RT10601SS-4A">4a</A> Klein S. Marek I. Normant J.-F. J. Org. Chem.  1994,  59:  2925 

<A NAME="RT10601SS-4B">4b</A> Mück-Lichtenfeld C. Ahlbrecht H. Tetrahedron  1996,  52:  10025 

<A NAME="RT10601SS-5">5</A> Review: Beak P. Meyers AI. Acc. Chem. Res.  1986,  19:  356 

<A NAME="RT10601SS-6">6</A>

The sense of diastereoselectivity, by which F is formed, depends on the configuration of intermediate E and the stereochemistry of the substitution step.

<A NAME="RT10601SS-7A">7a</A> Klein S. Marek I. Poisson J.-F. Normant JF. J. Am. Chem. Soc.  1995,  117:  8853 

<A NAME="RT10601SS-7B">7b</A> Norsikian S. Marek I. Poisson JF. Normant JF. J. Org. Chem.  1997,  62:  4898 

<A NAME="RT10601SS-7C">7c</A> Norsikian S. Marek I. Normant J.-F. Tetrahedron Lett.  1997,  38:  7523 

<A NAME="RT10601SS-7D">7d</A> Norsikian S. Marek I. Poisson JF. Normant JF. Chem.- Eur. J.  1999,  5:  2055 

For further enantioselective, intramolecular reactions of achiral lithium alkenyl compounds, being complexed at the cation by (-)-sparteine, see:

<A NAME="RT10601SS-8A">8a</A> Bailey WF. Mearly MJ. J. Am. Chem. Soc.  2000,  122:  6787 

<A NAME="RT10601SS-8B">8b</A> Sanz Gil G. Groth UM. J. Am. Chem. Soc.  2000,  122:  6789 

<A NAME="RT10601SS-9">9</A> Racemates: Hoppe D. Brönneke A. Synthesis  1982,  1045 

For preparation of chiral benzyl lithium compounds by deprotonation of optically active precursors, see:

<A NAME="RT10601SS-10A">10a</A> Hoppe D. Carstens A. Krämer T. Angew. Chem. Int. Ed. Engl.  1990,  29:  1424 

<A NAME="RT10601SS-10B">10b</A> Carstens A. Hoppe D. Tetrahedron  1994,  30:  6097 

<A NAME="RT10601SS-10C">10c</A> Derwing C. Hoppe D. Synthesis  1996,  149 

<A NAME="RT10601SS-10D">10d</A> Derwing C. Frank H. Hoppe D. Eur. J. Org. Chem.  1999,  3519 

<A NAME="RT10601SS-10E">10e</A> Hammerschmidt F. Hanninger A. Peric Simov B. Völlenkle H. Werner A. Eur. J. Org. Chem.  1999,  3511 

For further configurationally stable benzyllithiums:

<A NAME="RT10601SS-11A">11a</A> Hoppe D. Kaiser B. Stratmann O. Fröhlich R. Angew. Chem. Int. Ed. Engl.  1997,  36:  2784 

<A NAME="RT10601SS-11B">11b</A> Stratmann O. Kaiser B. Fröhlich R. Meyer O. Hoppe D. Eur. J. Org. Chem.  2001,  423 

Reviews:

<A NAME="RT10601SS-12A">12a</A> Hoppe D. Hense T. Angew. Chem. Int. Ed. Engl.  1997,  36:  2282 

<A NAME="RT10601SS-12B">12b</A> Beak P. Basu A. Gallagher DJ. Park YS. Thayumanavan S. Acc. Chem. Res.  1996,  29:  552 

<A NAME="RT10601SS-13">13</A> Superchi S. Sotomayor N. Miao G. Joseph B. Campbell MG. Snieckus V. Tetrahedron Lett.  1996,  37:  6061 

<A NAME="RT10601SS-14">14</A>

High simple diastereoselectivity may result from the syn-addition process.

<A NAME="RT10601SS-15">15</A> Hoppe D. Hanko R. Brönneke A. Lichtenberg F. van Hülsen E. Chem. Ber.  1985,  118:  2822 

<A NAME="RT10601SS-16">16</A> Heinl T. Retzow S. Hoppe D. Fraenkel G. Chem.- Eur. J.  1999,  5:  3464 

<A NAME="RT10601SS-17">17</A>

X-ray crystal structure analysis of 1d: formula C₂₁H₂₅NO₂, M = 323.42, colourless crystal 0.40 × 0.40 × 0.20 mm, a = 12.118(2), b = 13.509(2), c = 23.090(4) Å, β = 92.32(1)°, V = 3776.8(11) ų, ρ_calc = 1.138 g cm^-3, µ = 0.72 cm^-1, no absorption correction (0.994 ≤ C ≤ 0.999), Z = 8, monoclinic, space group P2₁/c (No. 14), λ = 0.71073 Å, T = 293 K, ω/2θ scans, 6700 reflections collected (+h,+k, ±l), [(sinθ)/λ] = 0.59 Å^-1, 6374 independent (R _int = 0.028) and 3227 observed reflections [I ≥ 2 σ(I)], 441 refined parameters, R = 0.048, wR ² = 0.114, max. residual electron density 0.45 (-0.23) e Å^-3, hydrogens calculated and refined as riding atoms, two almost identical molecules in the asymmetric unit, differences in the torsion angles C1-C2-O2-C3 and C31-C32-O32-C33. [36]

<A NAME="RT10601SS-18">18</A>

If not denoted otherwise in Tables: the first letter corresponds to the substrate and the second letter corresponds to the carbolithiation reagent.

<A NAME="RT10601SS-19">19</A>

X-ray crystal structure analysis of 9a: formula C₂₅H₃₅NO₂, M = 381.54, colourless crystal 0.70 × 0.50 × 0.30 mm, a = 29.416(5), c = 11.006(2) Å, V = 9524(3) ų, ρ_calc = 1.064 g cm^-3, µ = 0.66 cm^-1, empirical absorption correction via ψ scan data (0.928 ≤ C ≤ 0.999), Z = 16, tetragonal, space group I4₁/a (No. 88), λ = 0.71073 Å, T = 293 K, ω/2θ scans, 8176 reflections collected (+h, ±k,+l), [(sinθ)/λ] = 0.59 Å^-1, 4011 independent (R _int = 0.099) and 1859 observed reflections [I ≥ 2 σ(I)], 258 refined parameters, R = 0.062, wR ² = 0.161, max. residual electron density 0.18 (-0.17) e Å^-3, hydrogens calculated and refined as riding atoms. [36]

<A NAME="RT10601SS-20">20</A> See Ref. For a further example: Laqua H. Fröhlich R. Wibbeling B. Hoppe D. J. Organomet. Chem.  2001,  624:  96 

<A NAME="RT10601SS-21">21</A>

X-ray crystal structure analysis of 17: formula C₂₃H₃₅NO₄, M = 389.52, colourless crystal 0.30 × 0.25 × 0.15 mm, a = 10.689(1), b = 10.717(1), c = 10.953(1) Å, α = 101.53(1), β = 96.47(1), γ = 108.18(1)°, V = 1147.2(2) ų, ρ_calc = 1.128 g cm^-3, µ = 0.76 cm^-1, no absorption correction (0.978 ≤ T ≤ 0.989), Z = 2, triclinic, space group P1bar (No. 2), λ = 0.71073 Å, T = 293 K, ω and φ scans, 8217 reflections collected (±h, ±k, ±l), [(sinθ)/λ] = 0.65 Å^-1, 5220 independent (R _int = 0.020) and 4004 observed reflections [I ≥ 2 σ(I)], 261 refined parameters, R = 0.052, wR ² = 0.138, max. residual electron density 0.17 (-0.16) e Å^-3, hydrogens calculated and refined as riding atoms. [36]

<A NAME="RT10601SS-22">22</A> Tolbert LM. Martone DP. J. Org. Chem.  1983,  38:  1185 

<A NAME="RT10601SS-23A">23a</A> Wittig G. Bub O. Liebigs Ann. Chem.  1950,  566:  113 

<A NAME="RT10601SS-23B">23b</A> Wittig G. Gonsior L. Vogel H. Liebigs Ann. Chem.  1965,  688:  1 

<A NAME="RT10601SS-24">24</A> Fraenkel G. Geckle MJ. Kaylo A. Estes DW. J. Organomet. Chem.  1980,  197:  249 

<A NAME="RT10601SS-25">25</A>

Iodide 18 was prepared from 1-phenylprop-2-enol by carbamoylation, a deprotonation-γ-alkylation sequence with a ω-oxy-2-(tetrahydropyranyloxy)propyl iodide, deprotection of the hydroxy group and conversion to the iodide; see experimental section.

<A NAME="RT10601SS-26A">26a</A> Winkler HJS. Winkler H. J. Am. Chem. Soc.  1966,  88:  964 

<A NAME="RT10601SS-26B">26b</A> Winkler HJS. Winkler H. J. Am. Chem. Soc.  1966,  88:  969 

<A NAME="RT10601SS-26C">26c</A> Bailey WF. Patricia JJ. Del Gobbo VC. Jarret RM. Okarma PJ. J. Org. Chem.  1985,  50:  1999 

<A NAME="RT10601SS-26D">26d</A> Bailey WF. Nurmi TT. Patricia JJ. Wang W. J. Am. Chem. Soc.  1987,  109:  2442 

<A NAME="RT10601SS-26E">26e</A> Bailey WF. Khanolkar AD. Gavaskar K. Ovaska TV. Rossi K. Thiel Y. Wiberg KB. J. Am. Chem. Soc.  1991,  113:  5720 

<A NAME="RT10601SS-27">27</A>

See also footnote 15 in Ref. [13]

Pentyl phenyl ketone was submitted to an asymmetric reduction by (+)-diisopinocampheylchloroborane and the resulting alcohol was subsequently carbamoylated by N,N-diisopropylcarbamoyl chloride (4) in pyridine:

<A NAME="RT10601SS-28A">28a</A> Brown HC. Chandrasekharan J. Ramachandran PV. J. Am. Chem. Soc.  1988,  110:  1539 

<A NAME="RT10601SS-28B">28b</A>

See Ref. [15]

<A NAME="RT10601SS-29">29</A> Galinousky F. Knoth P. Fischer W. Monatsh. Chem.  1955,  86:  1014 

<A NAME="RT10601SS-30">30</A> Behrens K. Dissertation   University of Münster; Germany: 1997. 

<A NAME="RT10601SS-31A">31a</A> Benson SC. Cai P. Colon M. Haiza MA. Tokles M. Snyder JK. J. Org. Chem.  1988,  53:  5335 

<A NAME="RT10601SS-31B">31b</A> Würthwein E.-U. Behrens K. Hoppe D. Chem.- Eur. J.  1999,  5:  3459 

<A NAME="RT10601SS-32">32</A> Beak P. Kerrick ST. Wu S. Chu J. J. Am. Chem. Soc.  1999,  116:  3231 

<A NAME="RT10601SS-33">33</A> Peters JG. Dissertation   University of Münster; Germany: 2000. 

<A NAME="RT10601SS-34">34</A> Ramsden HE. Leebrick JR. Rosenberg SD. Miller EH. Walburn JJ. Balint AE. J. Org. Chem.  1957,  22:  1602 

<A NAME="RT10601SS-35">35</A> Cox GG. Moody CJ. Austin DJ. Padwa A. Tetrahedron  1993,  49:  5109 

<A NAME="RT10601SS-36A">36a</A> X-ray analysis

<A NAME="RT10601SS-36B">36b</A> X-ray data sets were collected with Enraf-Nonius CAD4 and Nonius Kappa CCD diffractometers, the later one equipped with a rotating anode generator Nonius FR591. Programs used: data collection EXPRESS (Nonius B.V., 1994) and COLLECT (Nonius B.V., 1998), data reduction MolEN (K. Fair, Enraf-Nonius B.V., 1990) and Denzo-SMN: Otwinowski Z. Minor W. Methods in Enzymology  1997,  276:  307 

<A NAME="RT10601SS-36C">36c</A> Absorption correction for CCD data SORTAV: Blessing RH. Acta Crystallogr.  1995,  A51:  33 

<A NAME="RT10601SS-36D">36d</A> Blessing RH. J. Appl. Crystallogr.  1997,  30:  421 

<A NAME="RT10601SS-36E">36e</A> Structure solution SHELXS-86 and SHELXS-97: Sheldrick GM. Acta Crystallogr.  1990,  A46:  467 

<A NAME="RT10601SS-36F">36f</A> Sheldrick GM. Structure refinement SHELXL-93 and SHELXL-97   Universität Göttingen; Germany: 1997. 

<A NAME="RT10601SS-36G">36g</A> Graphics: Keller E. SCHAKAL   Universität Freiburg; Germany: 1997. 

<A NAME="RT10601SS-36H">36h</A>

Crystallographic data (excluding structure factors) for the structure reported in this paper have been deposited with Cambridge Crystallographic Data Centre as supplementary publication No. CCDC-156957-156959. Copies of the data can be obtained free of charge on application to The Director, CCDC, 12 Union Road, Cambridge CB2 1EZ, UK (fax: int. code+44(1223)336-033; e-mail: [e-mail]).