Highly diastereoselective Cu(I) catalyzed conjugate addition of grignard reagents to 2-cyclohexene-1,4-dione mono(ethylenethioacetal)

Sonoda, S.; Houchigai, Hitoshi; Asaoka, Morio; Takei, Hisashi

doi:10.1016/s0040-4039(00)79835-2

Cited by 23 publications

(8 citation statements)

References 7 publications

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“…The SÐCsp 3 bond distances, although signi®cantly different in all three structures [1.860 (3) and 1.802 (6) A Ê in (IIa), 1.872 (3) and 1.805 (4) A Ê in (IIIa), and 1.848 (3) and 1.793 (4) A Ê in (IVb)], are in excellent agreement with the corresponding bond distances reported in the crystal structures of cyclohexanespiro-2 H -(1 H ,3 H -oxathiolan-5 H -one 3 H -oxide) (Frechina et al, 1992), (+)-(3S,4R)-6-phenyl-1-oxa-4-thiaspiro[4.5]decan-8-one (Sonoda et al, 1992), two derivatives of an oxathiaspirodecene (Parvez et al, 1997) and 2-(7-ethylidene-6-methyl-1-oxa-4-thiaspiro[4.5]dec-7-yl)ethanol (Parvez et al, 1998). The remaining bond distances and angles in the three structures are normal and agree well with the corresponding values reported for similar compounds contained in the Cambridge Structural Database (Allen & Kennard, 1993).…”

Section: Commentsupporting

confidence: 86%

Some Diels–Alder adducts of 6-vinyl-1-oxa-4-thiaspiro[4.5]dec-6-ene

2001

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6-Vinyl-1-oxa-4-thiaspiro[4.5]dec-6-ene has been reacted with dienophiles, such as N-phenylmaleimide (NPM), N-methyltriazoline-2,5-dione (MTAD) and dimethylacetylene dicarboxylate (DMAD), to assess the 1,3-diastereofacial selection caused by the acetal function. In each case, a mixture of two diastereoisomers was produced. The crystal structures of the products of the addition of NPM and MTAD syn to the acetal oxygen, 2-phenyl-2,3,3a,4,5,5a,6,7,8,9,9a,9b-dodecahydro-1H-benz[e]isoindole-6-spiro-2'-[1',3']oxathiolane-1,3-dione, C20H21NO3S, (IIa), and 2-methyl-5,7,8,9,10,10a-hexahydro-1H-1,2,4-triazolo[1,2-a]cinnoline-7-spiro-2'-[1',3']oxathiolane-1,3-dione, C13H17N3O3S, (IIIa), respectively, and the product of the addition of DMAD syn to the acetal sulfur, dimethyl 1,2,3,4,4a,7-hexahydronaphthalene-1-spiro-2'-[1',3']oxathiolane-5,6-dicarboxylate, C16H20O5S, (IVb), have been determined. All three structures are composed of independent molecules separated by normal van der Waals distances. The 1-oxa-4-thia heterocyclic ring has an envelope conformation in the three structures and the S-Csp(3) bond distances differ significantly from each other, as observed in comparable structures; the remaining molecular dimensions are as expected.

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Section: Commentsupporting

confidence: 86%

Some Diels–Alder adducts of 6-vinyl-1-oxa-4-thiaspiro[4.5]dec-6-ene

2001

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“…The SÐCsp 3 bond distances, although signi®cantly different from each other in (III) [1.880 (5) A Ê for SÐC3, and a mean of 1.811 (5) A Ê for SÐC1 and SÐC1*], are in excellent agreement with the corresponding bond distances in (VI) [1.878 (5) and 1.798 (6) A Ê ]. Similar non-equivalent SÐC bond distances have been reported in the crystal structures of cyclohexanespiro-2 H -(1 H ,3 Hoxathiolan-5 H -one 3 H -oxide) (Frechina et al, 1992), (+)-(3S,4R)-6-phenyl-1-oxa-4-thiaspiro[4.5]decan-8-one (Sonoda et al, 1992), two derivatives of an oxathiaspirodecene (Parvez et al, 1997) and 2-(7-ethylidene-6-methyl-1-oxa-4-thiaspiro[4.5]dec-7-yl)ethanol (Parvez et al, 1998).…”

supporting

confidence: 76%

Johnson orthoester Claisen rearrangement products of some (1-oxa-4-thiaspiro[4.5]dec-6-en-6-yl)alkanols

2001

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The crystal structures of two 1-oxa-4-thiaspiro[4.5]decane derivatives, ethyl 6-benzylidene-1-oxa-4-thiaspiro[4.5]decane-7-acetate, C19H24O3S, and (6-ethylidene-1-oxa-4-thiaspiro[4.5]decan-7-yl)ethyl 4-bromobenzoate, C19H23BrO3S, obtained under Johnson orthoester Claisen rearrangement conditions, exhibit different olefin geometry. Both structures are composed of independent molecules separated by normal van der Waals distances. The S-Csp(3) bond distances are significantly different from each other, as has been observed in similar structures; the remaining molecular dimensions are as expected.

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“…The transformation of 14 into 20 exclusively anti to the S is in support of the Cieplak mode of diastereoselection. The Cieplak mode of diastereoselection has previously been supported strongly by Halterman, 14 Johnson and Cieplak, 15 le Noble, 16 Mehta, 17 Meyers, 18 Sato, 19 Takei, 20 and several others. The Anh-Felkin model did not apply.…”

Section: Discussionmentioning

confidence: 80%

“…The reaction had proceeded almost exclusively anti to the sulfur. Sonoda et al have studied the conjugate addition of Grignard reagents to 1-oxa-4-thiaspiro[4.5]dec-6-ene-8-one, 4 , and reported anti to sulfur selection ranging from 76 to 96%. The Grignard additions to 2-acyl-1,3-oxathiane 7 proceed to furnish 8 with >95% anti to the sulfur selectivity .…”

Section: Introductionmentioning

confidence: 99%