메뉴 건너뛰기




Volumn , Issue 12, 1999, Pages 3369-3374

The effect of Lewis acids on the pinacol homocoupling reaction of aldehydes promoted by samarium diiodide

Author keywords

1,2 Diols; Carbonyl compounds; Lewis acid; Pinacol reaction; Samarium diiodide

Indexed keywords

ACID; ALDEHYDE; SAMARIUM; TITANIUM;

EID: 0032734080     PISSN: 1434193X     EISSN: None     Source Type: Journal    
DOI: 10.1002/(sici)1099-0690(199912)1999:12<3369::aid-ejoc3369>3.3.co;2-g     Document Type: Article
Times cited : (18)

References (42)
  • 1
    • 0001605152 scopus 로고
    • Pinacol coupling reactions
    • (Eds.: B. M. Trost, I. Fleming), Pergamon Press, Oxford
    • G.M. Robertson, "Pinacol Coupling Reactions", in Comprehensive Organic Synthesis Vol. 3 (Eds.: B. M. Trost, I. Fleming), Pergamon Press, Oxford, 1991, pp. 563-611.
    • (1991) Comprehensive Organic Synthesis , vol.3 , pp. 563-611
    • Robertson, G.M.1
  • 2
    • 0012020762 scopus 로고    scopus 로고
    • Stereoselection in pinacol coupling reactions of C=O and C=N double bonds
    • (Ed.: F. Cozzi), Società Chimica Italiana
    • M. Benaglia, L. Raimondi, "Stereoselection in Pinacol Coupling Reactions of C=O and C=N Double Bonds", in Seminars in Organic Synthesis (Ed.: F. Cozzi), Società Chimica Italiana, 1998, pp. 225-250.
    • (1998) Seminars in Organic Synthesis , pp. 225-250
    • Benaglia, M.1    Raimondi, L.2
  • 20
    • 0001692942 scopus 로고    scopus 로고
    • Some extremely interesting papers have recently been published regarding the stereoselectivity in the homocoupling of benzaldehyde tricarbonylchromium complexes in THF, and its dependence on the presence of HMPA as cosolvent: [11a] N. Tanigu-chi, N. Kaneta, M. Uemura, J. Org. Chem. 1996, 61, 6088-6089.
    • (1996) J. Org. Chem. , vol.61 , pp. 6088-6089
    • Tanigu-Chi, N.1    Kaneta, N.2    Uemura, M.3
  • 24
    • 0032538355 scopus 로고    scopus 로고
    • For a review on the use of Lewis acids in free radical reactions, see: P. Renaud, M. Gerster, Angew. Chem. Int. Ed. 1998, 37, 2562-2579.
    • (1998) Angew. Chem. Int. Ed. , vol.37 , pp. 2562-2579
    • Renaud, P.1    Gerster, M.2
  • 27
    • 85086352830 scopus 로고    scopus 로고
    • note
    • 4], 1a,b was obtained in 15% yield and a 35/65 synlanti ratio.
  • 28
    • 85086352290 scopus 로고    scopus 로고
    • note
    • 2 and HMPA, only unsaturated products were detected by NMR spectroscopy.
  • 29
    • 23544453995 scopus 로고    scopus 로고
    • Precomplexation of the reducing species before formation of the ketyl radical was demonstrated for some low-valent titanium-promoted couplings: A. Fürstner, B. Bogdanovic, Angew. Chem. Int. Ed. Engl. 1996, 35, 3442-3469.
    • (1996) Angew. Chem. Int. Ed. Engl. , vol.35 , pp. 3442-3469
    • Fürstner, A.1    Bogdanovic, B.2
  • 30
    • 0345005526 scopus 로고    scopus 로고
    • note
    • 4 completely inhibited the reaction, in agreement with our results (ref.[5a]).
  • 31
    • 85086352909 scopus 로고    scopus 로고
    • note
    • 2: we never observed diol formation, but only desulfurization products together with substitution reaction at the aromatic ring in some particular substrates.
  • 32
    • 85086353686 scopus 로고    scopus 로고
    • note
    • 2OH singlet of the corresponding alcohol (the most common by-product of these reactions).
  • 37
    • 0344574434 scopus 로고    scopus 로고
    • note
    • We have no evidences about the reaction mechanism operating in the different cases. Figure 1 shows a nucleophilic addition of the ketyl radical to a carbonyl, but direct coupling of two ketyls or nucleophilic addition of a C,O-dianion to the C = O cannot be ruled out. Complexation and/or chelation by the different metal species complicates the picture. For details on the different mechanisms proposed for the coupling reaction and a stereochemical discussion, see ref.[1][4]
  • 39
    • 0345436617 scopus 로고    scopus 로고
    • note
    • Interestingly enough, 8b arises from the coupling of two different enantiomers (S* + R*) of rac-2-phenylpropanal.


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.