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DOI: 10.1055/s-0029-1216999
Cyclopropanation with Dibromomethane under Grignard and Barbier Conditions
Publication History
Publication Date:
08 September 2009 (online)
Abstract
Tertiary Grignard reagents and dibromomethane efficiently cyclopropanate allylic (and certain homoallylic) magnesium and lithium alcoholates at ambient temperature in ether solvents. Lithium (homo)allyl alcoholates are directly cyclopropanated with magnesium and dibromomethane under Barbier conditions at higher temperatures. The reaction rates depend on the substitution pattern of the (homo)allylic alcoholates and on the counterion with lithium giving best results. Good to excellent syn-selectivities are obtained from α-substituted (homo)allyl alcohols. In tandem reactions, cyclopropyl carbinols are obtained from allyloxylithium or -magnesium intermediates, generated in situ by alkylation of conjugated aldehydes, ketones, and esters as well as from allyl esters and carbonates or vinyloxiranes. [¹]
Key words
cyclopropanation - Barbier conditions - Grignard addition - alkyllithium addition - dibromomethane
- 1
Brunner G.Eberhard L.Oetiker J.Schröder F. J. Org. Chem. 2008, 73: 7543 - 2 Review:
Charette AB.Beauchemin A. Org. React. 2001, 58: 1 -
4a
Friedrich EC.Domek JM.Pong RY. J. Org. Chem. 1985, 50: 4640 -
4b
Friedrich EC.Lewis EJ. J. Org. Chem. 1990, 55: 2491 -
4c
Friedrich EC.Niyati-Shirkhodaee F. J. Org. Chem. 1991, 56: 2202 -
5a
Bolm C.Pupowicz D. Tetrahedron Lett. 1997, 38: 7349 -
5b
Pupowicz D. Dissertation Philipps-Universität Marburg; Germany: 1997. -
6a
Villiéras J. C. R. Hebd. Seances Acad. Sci. 1965, 261: 4137 -
6b
Villiéras J. Bull. Chem. Soc. Fr. 1967, 5: 1520 - 7
Hoveyda AM.Evans DA.Fu GC. Chem. Rev. 1993, 93: 1307 ; and references therein - The formation of these byproducts shows that radical mechanisms are at least partially involved:
-
8a
Ashby EC.Deshpande AK.Doctorovich F. J. Org. Chem. 1994, 59: 6223 -
8b
Walton JC. In Houben-Weyl Vol. E17c:de Meijere A. Thieme; Stuttgart: 1997. p.2438 -
10a
Ratier M.Castaing M.Godet J.-Y.Pereyre M. J. Chem. Res., Synop. 1978, 179 -
10b
Molander GA.Etter JB. J. Org. Chem. 1987, 52: 3942 -
10c
Molander GA.Harring LS. J. Org. Chem. 1989, 54: 3525 - Preparation of substrates 1 according to the literature:
-
12a
1a:
Bajgrowicz JA.Frank I.Frater G.Hennig M. Helv. Chim. Acta 1998, 81: 1349 -
12b
Schröder F. inventors; WO 2006,066,436. 1b: ; Chem. Abstr. 2006, 145, 103855 -
12c
1c:
Tamura M.Suzukamo G. Tetrahedron Lett. 1981, 22: 577 -
12d
Tamura M,Suzukamo G, andHirose K. inventors; EP 0,029,603. 1c: ; Chem. Abstr. 1981, 95, 204220 -
12e
1d: see ref. 1.
-
12f
Levorse AT. inventors; US 5,234,902. 1e: ; Chem. Abstr. 1993, 119, 210271 -
12g
Bajgrowicz JA,Bringhen A,Frater G, andMueller U. inventors; EP 743,297. 1f: ; Chem. Abstr. 1996, 126, 103856 -
12h
Kaiser R, andLamparsky D. inventors; EP 0,045,453. 1g: ; Chem. Abstr. 1982, 96, 199080 -
12i
Berg-Schultz K,Bajgrowicz JA, andBaudin J. inventors; WO 2005,026,092. 1h: ; Chem. Abstr. 2005, 142, 336041 -
12j
1i:
Jacob P.Brown HC. J. Org. Chem. 1977, 42: 579 -
12k
Martin A. inventors; EP 770,671. 1j: ; Chem. Abstr. 1997, 126, 334220 -
12l
1k:
Traas PC.Boelens H. Rec. Trav. Chim. Pays-Bas 1973, 92: 985 -
12m
1l:
Arbuzov BA.Isaeva ZG.Timoshina TN.Efremov YY. Russ. J. Org. Chem. 1993, 29: 1647 - 13
Watson SC,Malpass DB, andYeargin GS. inventors; DE 2,430,287. ; Chem. Abstr. 1975, 83, 27544 - Preparation of the substrates:
-
14a
5r:
Ullrich FW.Rotscheidt K.Breitmaier E. Chem. Ber. 1986, 119: 1737 -
14b
Hall JB, andWiegers WJ. inventors; US 4010207. 5s: ; Chem. Abstr. 1977, 87, 5396 - 15
Fanta WI.Erman WF. J. Org. Chem. 1968, 33: 1656 - 16
Cheng D.Kreethadumrongdat T.Cohen T. Org. Lett. 2001, 3: 2121 - Preparation of substrates 7 according to the literature:
-
18a
7a:
Jurkauskas V.Sadighi JP.Buchwald SL. Org. Lett. 2003, 5: 2417 -
18b
7c:
Berube G.Fallix AG. Can. J. Chem. 1991, 69: 77 -
18c
7d:
Trost BM.Keeley DE. J. Am. Chem. Soc. 1976, 98: 248 -
18d
7e:
Berthelot P.Vaccher C.Devergnies M.Flouquet N.Debaert M. J. Heterocycl. Chem. 1988, 25: 1525 - 19
Rathke MW.Nowak M. J. Org. Chem. 1985, 50: 2624 - 20
Agarwal VK.Thappa RK.Agarwal SG.Mehra MS.Dhar KL.Atal CK. Indian Perfumer 1983, 27: 112 - 21
Barras J.-P.Bourdin B.Schröder F. Chimia 2006, 60: 574 -
22a
Tamura M.Suzukamo G. Tetrahedron Lett. 1981, 22: 577 -
22b
Netland P. Org. Prep. Proced. Int. 1980, 12: 261 ; and references therein - 23
Sakaguchi T,Nagashima K, andYoshida T. inventors; JP 49,047,345. ; Chem. Abstr. 1974, 81, 104862 - 24 Alternative deprotonation reagents
such as NaH or MeMgCl were less efficient. Alternative dihalides
such as ClCH2Br, ClCH2I, and CH2I
converted 1b similarly into 2b but
without remote cyclopropanation to 2a.
Evidence for exchange reactions between lithium alkoxides and Grignard
reagents:
Micha-Screttas M.Constantinos G.Steele BR.Heropoulos GA. Tetrahedron Lett. 2002, 43: 4871 -
27a
Roquet F.Sevin A.Chodkiewicz W. C. R. Seances Acad. Sci., Ser. C 1970, 848 -
27b
Ratier M.Castaing M.Godet J.-Y.Pereyre M. J. Chem. Res., Miniprint 1978, 2309 - 29
Pretsch E.Bühlmann P.Affolter C. Structure Determination of Organic Compounds Springer Verlag; Berlin: 2000. p.202 - 30
Narula APS, andArruda EM. inventors; US 20060,189,510. ; Chem. Abstr. 2006, 145, 255592 - 31
Bajgrowicz JA, andFrater G. inventors; EP 0,801,049. ; Chem. Abstr. 1997, 127, 358652
References:
The reactivity order of dihalomethanes is in accordance with that of the radical halogen abstraction from these compounds.
9Among other byproducts identified by GC/MS: 2,2,4,4-tetramethylpentane (CAS 1070-87-7), 2,2,6,6-tetramethyl-4-methyleneheptane (CAS 141-70-8), 2-tert-butyltetra-hydrofuran (CAS 38624-45-2), 2,2-dimethyldecane (CAS 17302-37-3), 2,2,8-trimethyldecane (CAS 62238-01-1), 2,2-dimethylundecane (CAS 17312-64-0), tert-butyl bromide (CAS 507-19-7), 1-bromo-2,2-dimethylpropane (CAS 630-17-1), 2-bromotetrahydrofuran (CAS 59253-21-3), 3-bromo-2,2,4,4-tetramethylpentane (CAS 107713-49-5).
11Allylic alcohols, which underwent incomplete conversions with the system CH2Br2 (3 equiv)/t-BuMgCl (4 equiv) (GC conversion to the corresponding cyclopropanes after 18 h in brackets): (E)-hex-2-enol (35%), (Z)-hex-2-enol (65%), nonadienol (50%), geraniol (50%), nerol (10%), oct-1-en-3-ol (50%), linalool (40%), and nerolidol (50%).
172-Hexylcyclopent-2-enone = isojasmone B 11. Commercial available from Oxford Chemicals.
25A possible explanation for this rate enhancement is the more covalent character of the Mg-O bond of the MgX-alcoholates versus the lithium alcoholate ion pair. For mechanistic details see ref. 1.
26The syn-selectivities are in accord with a staggered Houk model.²7
28GC-analysis on a 5% phenyl-95% dimethylpolysiloxane column.