GB1591968A - Process for the preparation of 8-oxoacetals - Google Patents
Process for the preparation of 8-oxoacetals Download PDFInfo
- Publication number
- GB1591968A GB1591968A GB19655/78A GB1965578A GB1591968A GB 1591968 A GB1591968 A GB 1591968A GB 19655/78 A GB19655/78 A GB 19655/78A GB 1965578 A GB1965578 A GB 1965578A GB 1591968 A GB1591968 A GB 1591968A
- Authority
- GB
- United Kingdom
- Prior art keywords
- methyl
- process according
- carbon atoms
- hydrogen
- alkyl
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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- 238000000034 method Methods 0.000 title claims description 28
- 238000002360 preparation method Methods 0.000 title claims description 9
- 239000002841 Lewis acid Substances 0.000 claims abstract description 11
- 150000007517 lewis acids Chemical class 0.000 claims abstract description 11
- WEVYAHXRMPXWCK-UHFFFAOYSA-N Acetonitrile Chemical compound CC#N WEVYAHXRMPXWCK-UHFFFAOYSA-N 0.000 claims description 21
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims description 21
- 239000001257 hydrogen Substances 0.000 claims description 21
- 229910052739 hydrogen Inorganic materials 0.000 claims description 21
- -1 tin halide Chemical class 0.000 claims description 21
- 125000000217 alkyl group Chemical group 0.000 claims description 20
- 125000004432 carbon atom Chemical group C* 0.000 claims description 20
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 claims description 17
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 claims description 14
- JIAARYAFYJHUJI-UHFFFAOYSA-L zinc dichloride Chemical compound [Cl-].[Cl-].[Zn+2] JIAARYAFYJHUJI-UHFFFAOYSA-L 0.000 claims description 13
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 12
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 claims description 11
- 238000006243 chemical reaction Methods 0.000 claims description 10
- 229930195733 hydrocarbon Natural products 0.000 claims description 9
- 239000000203 mixture Substances 0.000 claims description 9
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 8
- 239000004215 Carbon black (E152) Substances 0.000 claims description 8
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 claims description 8
- 229910052753 mercury Inorganic materials 0.000 claims description 8
- 239000012071 phase Substances 0.000 claims description 7
- 229910000027 potassium carbonate Inorganic materials 0.000 claims description 7
- 239000002904 solvent Substances 0.000 claims description 7
- 239000011592 zinc chloride Substances 0.000 claims description 7
- 235000005074 zinc chloride Nutrition 0.000 claims description 7
- AIUVIHYATZICHW-UHFFFAOYSA-N 5,5-diethoxy-3-methylpent-3-en-2-one Chemical compound CCOC(OCC)C=C(C)C(C)=O AIUVIHYATZICHW-UHFFFAOYSA-N 0.000 claims description 6
- UIIMBOGNXHQVGW-UHFFFAOYSA-M Sodium bicarbonate Chemical compound [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 claims description 6
- 239000003054 catalyst Substances 0.000 claims description 6
- 150000001875 compounds Chemical class 0.000 claims description 6
- 125000001997 phenyl group Chemical group [H]C1=C([H])C([H])=C(*)C([H])=C1[H] 0.000 claims description 6
- 229920006395 saturated elastomer Polymers 0.000 claims description 6
- 238000003756 stirring Methods 0.000 claims description 6
- 239000007864 aqueous solution Substances 0.000 claims description 5
- 150000002431 hydrogen Chemical class 0.000 claims description 5
- TXBMCLDHFRIQLA-UHFFFAOYSA-N trimethyl(3-methylbuta-1,3-dienoxy)silane Chemical compound CC(=C)C=CO[Si](C)(C)C TXBMCLDHFRIQLA-UHFFFAOYSA-N 0.000 claims description 5
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 claims description 4
- 229910052786 argon Inorganic materials 0.000 claims description 4
- 238000004587 chromatography analysis Methods 0.000 claims description 4
- 125000000113 cyclohexyl group Chemical group [H]C1([H])C([H])([H])C([H])([H])C([H])(*)C([H])([H])C1([H])[H] 0.000 claims description 4
- 125000001511 cyclopentyl group Chemical group [H]C1([H])C([H])([H])C([H])([H])C([H])(*)C1([H])[H] 0.000 claims description 4
- 125000004435 hydrogen atom Chemical group [H]* 0.000 claims description 4
- 239000011541 reaction mixture Substances 0.000 claims description 4
- PYOKUURKVVELLB-UHFFFAOYSA-N trimethyl orthoformate Chemical compound COC(OC)OC PYOKUURKVVELLB-UHFFFAOYSA-N 0.000 claims description 4
- MXVNUXZQRXWKBU-UHFFFAOYSA-N 5,5-dimethoxy-3-methylpent-3-en-2-one Chemical compound COC(C=C(C(C)=O)C)OC MXVNUXZQRXWKBU-UHFFFAOYSA-N 0.000 claims description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical group [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 3
- 125000003342 alkenyl group Chemical group 0.000 claims description 3
- 125000003710 aryl alkyl group Chemical group 0.000 claims description 3
- 229910052799 carbon Inorganic materials 0.000 claims description 3
- 150000002148 esters Chemical group 0.000 claims description 3
- 238000010992 reflux Methods 0.000 claims description 3
- 229910000030 sodium bicarbonate Inorganic materials 0.000 claims description 3
- 235000017557 sodium bicarbonate Nutrition 0.000 claims description 3
- 239000000243 solution Substances 0.000 claims description 3
- HPGGPRDJHPYFRM-UHFFFAOYSA-J tin(iv) chloride Chemical compound Cl[Sn](Cl)(Cl)Cl HPGGPRDJHPYFRM-UHFFFAOYSA-J 0.000 claims description 3
- 229910052725 zinc Inorganic materials 0.000 claims description 3
- 239000011701 zinc Substances 0.000 claims description 3
- UIIMBOGNXHQVGW-DEQYMQKBSA-M Sodium bicarbonate-14C Chemical compound [Na+].O[14C]([O-])=O UIIMBOGNXHQVGW-DEQYMQKBSA-M 0.000 claims description 2
- 229910021627 Tin(IV) chloride Inorganic materials 0.000 claims description 2
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 2
- CIUQDSCDWFSTQR-UHFFFAOYSA-N [C]1=CC=CC=C1 Chemical group [C]1=CC=CC=C1 CIUQDSCDWFSTQR-UHFFFAOYSA-N 0.000 claims description 2
- 150000001338 aliphatic hydrocarbons Chemical class 0.000 claims description 2
- 238000009835 boiling Methods 0.000 claims description 2
- 238000001914 filtration Methods 0.000 claims description 2
- 238000001030 gas--liquid chromatography Methods 0.000 claims description 2
- 150000002825 nitriles Chemical class 0.000 claims description 2
- 239000012074 organic phase Substances 0.000 claims description 2
- 239000012047 saturated solution Substances 0.000 claims description 2
- 239000011780 sodium chloride Substances 0.000 claims description 2
- 238000004809 thin layer chromatography Methods 0.000 claims description 2
- 229910052723 transition metal Inorganic materials 0.000 claims description 2
- 150000003624 transition metals Chemical group 0.000 claims description 2
- 239000012442 inert solvent Substances 0.000 claims 1
- KAKZBPTYRLMSJV-UHFFFAOYSA-N vinyl-ethylene Natural products C=CC=C KAKZBPTYRLMSJV-UHFFFAOYSA-N 0.000 claims 1
- 150000002576 ketones Chemical class 0.000 abstract description 4
- 150000002905 orthoesters Chemical class 0.000 abstract description 4
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 abstract 1
- 150000001299 aldehydes Chemical class 0.000 abstract 1
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 description 6
- 239000000047 product Substances 0.000 description 5
- 239000000376 reactant Substances 0.000 description 5
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 3
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 238000009833 condensation Methods 0.000 description 3
- 230000005494 condensation Effects 0.000 description 3
- 125000002485 formyl group Chemical class [H]C(*)=O 0.000 description 3
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical compound CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 description 3
- 238000003786 synthesis reaction Methods 0.000 description 3
- HEDRZPFGACZZDS-UHFFFAOYSA-N Chloroform Chemical compound ClC(Cl)Cl HEDRZPFGACZZDS-UHFFFAOYSA-N 0.000 description 2
- IMNFDUFMRHMDMM-UHFFFAOYSA-N N-Heptane Chemical compound CCCCCCC IMNFDUFMRHMDMM-UHFFFAOYSA-N 0.000 description 2
- 238000005481 NMR spectroscopy Methods 0.000 description 2
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 description 2
- 150000001241 acetals Chemical class 0.000 description 2
- 125000000753 cycloalkyl group Chemical group 0.000 description 2
- 150000002084 enol ethers Chemical class 0.000 description 2
- 150000002170 ethers Chemical class 0.000 description 2
- WBJINCZRORDGAQ-UHFFFAOYSA-N formic acid ethyl ester Natural products CCOC=O WBJINCZRORDGAQ-UHFFFAOYSA-N 0.000 description 2
- 230000007062 hydrolysis Effects 0.000 description 2
- 238000006460 hydrolysis reaction Methods 0.000 description 2
- 125000001449 isopropyl group Chemical group [H]C([H])([H])C([H])(*)C([H])([H])[H] 0.000 description 2
- 125000004108 n-butyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 2
- VZGDMQKNWNREIO-UHFFFAOYSA-N tetrachloromethane Chemical compound ClC(Cl)(Cl)Cl VZGDMQKNWNREIO-UHFFFAOYSA-N 0.000 description 2
- GKASDNZWUGIAMG-UHFFFAOYSA-N triethyl orthoformate Chemical compound CCOC(OCC)OCC GKASDNZWUGIAMG-UHFFFAOYSA-N 0.000 description 2
- DYLIWHYUXAJDOJ-OWOJBTEDSA-N (e)-4-(6-aminopurin-9-yl)but-2-en-1-ol Chemical compound NC1=NC=NC2=C1N=CN2C\C=C\CO DYLIWHYUXAJDOJ-OWOJBTEDSA-N 0.000 description 1
- 125000003903 2-propenyl group Chemical group [H]C([*])([H])C([H])=C([H])[H] 0.000 description 1
- CPELXLSAUQHCOX-UHFFFAOYSA-M Bromide Chemical compound [Br-] CPELXLSAUQHCOX-UHFFFAOYSA-M 0.000 description 1
- WKBOTKDWSSQWDR-UHFFFAOYSA-N Bromine atom Chemical compound [Br] WKBOTKDWSSQWDR-UHFFFAOYSA-N 0.000 description 1
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- XDTMQSROBMDMFD-UHFFFAOYSA-N Cyclohexane Chemical compound C1CCCCC1 XDTMQSROBMDMFD-UHFFFAOYSA-N 0.000 description 1
- SNRUBQQJIBEYMU-UHFFFAOYSA-N Dodecane Natural products CCCCCCCCCCCC SNRUBQQJIBEYMU-UHFFFAOYSA-N 0.000 description 1
- 238000004566 IR spectroscopy Methods 0.000 description 1
- FXHOOIRPVKKKFG-UHFFFAOYSA-N N,N-Dimethylacetamide Chemical compound CN(C)C(C)=O FXHOOIRPVKKKFG-UHFFFAOYSA-N 0.000 description 1
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 1
- VNDYJBBGRKZCSX-UHFFFAOYSA-L Zinc bromide Inorganic materials Br[Zn]Br VNDYJBBGRKZCSX-UHFFFAOYSA-L 0.000 description 1
- 125000004036 acetal group Chemical group 0.000 description 1
- 239000003377 acid catalyst Substances 0.000 description 1
- 150000004945 aromatic hydrocarbons Chemical class 0.000 description 1
- 125000001797 benzyl group Chemical group [H]C1=C([H])C([H])=C(C([H])=C1[H])C([H])([H])* 0.000 description 1
- 229910052796 boron Inorganic materials 0.000 description 1
- GDTBXPJZTBHREO-UHFFFAOYSA-N bromine Substances BrBr GDTBXPJZTBHREO-UHFFFAOYSA-N 0.000 description 1
- 229910052794 bromium Inorganic materials 0.000 description 1
- 150000001649 bromium compounds Chemical class 0.000 description 1
- OPEGYIVFJNBLRP-UHFFFAOYSA-N buta-1,3-dienoxy(triethyl)silane Chemical compound CC[Si](CC)(CC)OC=CC=C OPEGYIVFJNBLRP-UHFFFAOYSA-N 0.000 description 1
- UQGOYQLRRBTVFM-UHFFFAOYSA-N buta-1,3-dienoxy(trimethyl)silane Chemical compound C[Si](C)(C)OC=CC=C UQGOYQLRRBTVFM-UHFFFAOYSA-N 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 150000003857 carboxamides Chemical class 0.000 description 1
- 239000000460 chlorine Substances 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 150000001805 chlorine compounds Chemical class 0.000 description 1
- 239000007859 condensation product Substances 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 125000003438 dodecyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 150000002085 enols Chemical class 0.000 description 1
- RSIHJDGMBDPTIM-UHFFFAOYSA-N ethoxy(trimethyl)silane Chemical compound CCO[Si](C)(C)C RSIHJDGMBDPTIM-UHFFFAOYSA-N 0.000 description 1
- FGCLOJOLJQDQOG-UHFFFAOYSA-N ethoxymethanediol Chemical class CCOC(O)O FGCLOJOLJQDQOG-UHFFFAOYSA-N 0.000 description 1
- 150000008282 halocarbons Chemical class 0.000 description 1
- 125000005843 halogen group Chemical group 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- ZYRRKOAAQBHXBT-UHFFFAOYSA-N hexa-1,3-dienoxy(trimethyl)silane Chemical compound CCC=CC=CO[Si](C)(C)C ZYRRKOAAQBHXBT-UHFFFAOYSA-N 0.000 description 1
- 125000004051 hexyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 238000005984 hydrogenation reaction Methods 0.000 description 1
- 238000002329 infrared spectrum Methods 0.000 description 1
- 239000000543 intermediate Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- OFBQJSOFQDEBGM-UHFFFAOYSA-N n-pentane Natural products CCCCC OFBQJSOFQDEBGM-UHFFFAOYSA-N 0.000 description 1
- 125000004123 n-propyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- 125000002347 octyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 125000001147 pentyl group Chemical group C(CCCC)* 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 229920000728 polyester Polymers 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 229920001296 polysiloxane Polymers 0.000 description 1
- 229920002635 polyurethane Polymers 0.000 description 1
- 239000004814 polyurethane Substances 0.000 description 1
- FVSKHRXBFJPNKK-UHFFFAOYSA-N propionitrile Chemical compound CCC#N FVSKHRXBFJPNKK-UHFFFAOYSA-N 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- BDHFUVZGWQCTTF-UHFFFAOYSA-N sulfonic acid Chemical compound OS(=O)=O BDHFUVZGWQCTTF-UHFFFAOYSA-N 0.000 description 1
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 1
- XJDNKRIXUMDJCW-UHFFFAOYSA-J titanium tetrachloride Chemical compound Cl[Ti](Cl)(Cl)Cl XJDNKRIXUMDJCW-UHFFFAOYSA-J 0.000 description 1
- 125000003944 tolyl group Chemical group 0.000 description 1
- CGSRCFXAHZCJKA-UHFFFAOYSA-N trimethyl(2-methylbuta-1,3-dienoxy)silane Chemical compound C=CC(C)=CO[Si](C)(C)C CGSRCFXAHZCJKA-UHFFFAOYSA-N 0.000 description 1
- NGEIBAZWTYUUEI-UHFFFAOYSA-N trimethyl(2-methylhexa-1,3-dienoxy)silane Chemical compound CCC=CC(C)=CO[Si](C)(C)C NGEIBAZWTYUUEI-UHFFFAOYSA-N 0.000 description 1
- UDECNVKNELCBHM-UHFFFAOYSA-N trimethyl(3-methylidenepent-1-enoxy)silane Chemical compound C(C)C(C=CO[Si](C)(C)C)=C UDECNVKNELCBHM-UHFFFAOYSA-N 0.000 description 1
- YYBUYNRYATXXAT-UHFFFAOYSA-N trimethyl(3-methylpenta-1,3-dienoxy)silane Chemical compound CC=C(C)C=CO[Si](C)(C)C YYBUYNRYATXXAT-UHFFFAOYSA-N 0.000 description 1
- WKTNFXWRUHDTFA-UHFFFAOYSA-N trimethyl(4-methylpenta-1,3-dienoxy)silane Chemical compound CC(C)=CC=CO[Si](C)(C)C WKTNFXWRUHDTFA-UHFFFAOYSA-N 0.000 description 1
- QOMHQPJJGFLALB-UHFFFAOYSA-N trimethyl(5-methylhexa-3,5-dien-3-yloxy)silane Chemical compound CC(=C)C=C(CC)O[Si](C)(C)C QOMHQPJJGFLALB-UHFFFAOYSA-N 0.000 description 1
- RUQSUPCMWLPYOB-UHFFFAOYSA-N trimethyl(penta-2,4-dien-2-yloxy)silane Chemical compound C[Si](C)(C)OC(C)=CC=C RUQSUPCMWLPYOB-UHFFFAOYSA-N 0.000 description 1
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 1
- 229920002554 vinyl polymer Polymers 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 125000005023 xylyl group Chemical group 0.000 description 1
- 229940102001 zinc bromide Drugs 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C47/00—Compounds having —CHO groups
- C07C47/20—Unsaturated compounds having —CHO groups bound to acyclic carbon atoms
- C07C47/277—Unsaturated compounds having —CHO groups bound to acyclic carbon atoms containing ether groups, groups, groups, or groups
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/51—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by pyrolysis, rearrangement or decomposition
- C07C45/511—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by pyrolysis, rearrangement or decomposition involving transformation of singly bound oxygen functional groups to >C = O groups
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
An ortho ester of an alcohol is reacted, in the presence of a Lewis acid, with a 1,3-dieneoxysilane derived from an enolisable alpha , beta - or beta , gamma -ethylenic aldehyde or ketone. The ethylenic delta -oxoacetals can be used especially for preparing delta -dicarbonyl compounds and in particular delta -dialdehydes.
Description
(54) PROCESS FOR THE PREPARATION OF bOXOACETALS (71) We, RHONE-POULENC INDUSTRIES, a French Body Corporate, of 22 avenue Montaigne, 75008 Paris, France, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The present invention relates to the preparation of b-oxoacetals containing an ethylenic double bond in the A,y position relative to the acetal group, and to novel b-oxoacetals thus obtained.
It is known that ortho-esters and, in particular ortho-formates of lower afkanols can be condensed, in the presence of Lewis acids, with enol derivatives of aldehydes or of ketones, such as enol ethers and enoxysilanes. In the case of enol ethers, the reaction carried out in the presence of Lewis acids such as BF3, ZnCl2 and FeCI3 leads to the formation of bis-p-acetals which, after hydrolysis, provide a route to p-dicarbonyl compounds (compare L. S. Povarov, Russ. Chem. Rev., 34, pages 649-650 [1965]; Mezheritski et al., Russ. Chem. Rev., 42, pages 396-397 [1973]; and F. Effenberger, Angew. Chem. Internat. Ed., 8,pages295-312 [1969]).
The condensation of enoxysilanes with ortho-formates in the presence of large amounts of titanium tetrachloride gives rise to the formation of A-oxoacetals (compare T. Mukayama et al., Chem. Letters, 1974, pages 15-16; and ibid., 1976, pages 1,033-1,036). Povarov (loc. cit.) points out that alkoxydienes are incapable of reacting with ortho-esters to form condensation products, whereas they react easily with acetals (in particular acetals of a"B-ethylenic.aldebydes), in the presence of Lewis acids, to give a,-ethylenic X-alkoxyacetals (compare also S. M. Makin,
Russ. Chem. Rev., 38, pages 237-248 [1969]). Contrary to all expectations, it has been found that 1,3-dienoxysilanes react with ortho-esters.
The present invention more particularly provides a process for the preparation of A,y-ethylenic b-oxoacetals, which comprises reacting an ortho-formate ester of an (alkanol), in the presence of a Lewis acid, with a 1 ,3-dienoxysilane of the formula:
in which each of R1, R2, R3, R4 and R5, which are identical or different, is hydrogen or a hydrocarbon radical, R6 is a hydrocarbon radical, and n is an integer from 1 to 3. (In the following text, the term "dienoxysilane" means a 1,3-dienoxysilane df the aforesaid formula). The said ortho-formate ester is preferably an ester of an alkanol of the formula: H-C(OR)3 (Il) in which R is straight or branched alkyl of 1 to 4 carbon atoms.
The products of this new process are the p,y-ethylenic b-oxoacetals of the formula:
in which R is straight or branched alkyl, preferably of I to 4 carbon atoms, and
each of R1, R2, R3, R4 and R5, which are identical or different, is hydrogen or a
hydrocarbon radical.
In the formulae (I) to (III), the various symbols can more particularly
represent the following: R to R5, which are identical or different, may represent hydrocarbon radicals havihg from 1 to 20 carbon atoms each, such as straight or branched alkyl, straight
or branched alkenyl, cycloalkyl of 5 to 6 cyclic carbon atoms, or phenyl:
R may represent methyl ethyl, n-propyl, isopropyl or n-butyl; and
R6 may represent a straight or branched alkyl of from I to 4 carbon atoms, such as one of those mentioned above, cycloalkyl (e.g. cyclopentyl or cyclohexyl), phenyl, or arylalkyl (e.g. benzyl or p-phenylethyl). Although R6 can have the most varied meanings, it is preferable for practical reasons to employ dienoxysilanes of the formula (1), in which R6 represents methyl, ethyl or phenyl. When n is 2 or 3, the radicals Ra can be identical or different.
Rl to R5 can more particularly represent alkyl radicals such as methyl, ethyl, npropyl, isopropyl, n-butyl, sec.-butyl, pentyl, hexyl, octyl or dodecyl, alkenyl radicals containing one or more ethylenic double bonds, such as vinyl, propen-l-yl, allyl, buten-l-yl, buten-2-yl or isobutenyl provided preferably that R2 does not contain an ethylenic double bond conjugated with the enol double bond, and R4 and R5 do not contain a double bond conjugated with that of the carbon to which they are attached or cyclohexyl, cyclopentyl, phenyl, tolyl, or xylyl.
R is preferably methyl or ethyl.
R1 preferably is alkyl of 1 to 4 carbon atoms or, even more preferably, hydrogen;
R2, R3, R4 and Rs preferably represent hydrogen or alkyl of 1 to 4 carbon atoms especially methyl or ethyl. It is especially preferred for R1, R2 and R3 to be hydrogen, one of R4 and R5 to be hydrogen and the other hydrogen or methyl, Ra is preferably methyl or ethyl and n is preferably 3.
The dienoxysilanes of the formula (I), which are used in the process of the invention, are generally known products which can be easily prepared by reacting a mono-, di-, or tri-halogenosilane of the general formula: (R6)nS(X)4-N in which R6 and n are as defined above and X represents a halogen atom (chlorine or bromine), with an enolisable cu,p- or B,y-ethylenic aldehyde or ketone, in the presence of zinc chloride and a hydroacid acceptor in accordance with the process described in Belgian Patent 670,769
Suitable enoxysilanes of the formula (I) include the following:
A. Those derived from aldehydes. such as. (1,3 - butadienyloxy) trimethylsilane, (1,3 - butadienyloxy) - triethylsilane, bis - (1,3 - butadienyloxy) dimethylsilane, (3 - methyl - 1,3 - butadienyloxy) - trimethylsilane, (3 - ethyl
1,3 - butadienyloxy) - trimethylsilane, (2 - methyl - 1,3 - butadienyloxy) trimethylsilane, (4 - methyl - 1,3 - pentadienyloxy) - trimethylsilane, (1,3 hexadienyloxy)- trimethylsilane, (3 - methyl - 1,3 - pentadienyloxy) trimethylsilane, (2 - methyl - 1,3 - hexadienyloxy) - trimethylsilane and (3,4 dimethyl - 1,3 - pentadienyloxy) - trimethylsilane, and
B. Those derivedfrom ketones, such as: 4 - trimethylsilyloxy - 1,3 - pentadiene, 4 - trimethylsilyloxy - 1,3 - hexadiene, 2 methyl - 4 - trimethylsiloxy - 1,3 pentadiene, 3 - methyl - 4 - trimethylsilyloxy - 1,3 - pentadiene and 2 - methyl 4 - trimethylsilyloxy - 1,3 - hexadiene.
Suitable ortho-formates for the process of the invention, are preferably the methyl and ethyl ortho-formates which provide a route to ,y-ethylenic - oxoacetals which, by hydrolysis, lead to ,y-ethylenic b-ketoaldehydes and to ethylenic b-dialdehydes.
It is believed that the condensation of ortho-formates with dienoxysilanes in accordance with the invention can be represented by the following equation:
The alkoxysilane formed during the reaction is a by-product of industrial value; in fact, it can be used in the synthesis of polysiloxane polymers. It can also be converted into an organohalogenosilane by the customary processes, and the latter can be used again for the preparation of the starting enoxysilanes.
The amounts of dienoxysilane and ortho-formate which are employed to carry out the reaction can be near the stoichiometric amounts, that is to say about one mol of ortho-formate per dienoxy group present in the dienoxysilane, or they can deviate substantially from the stoichiometric amounts, it being possible to use an excess of one or other of the reactants, and preferably an excess of ortho-formate.
The amount of ortho-formate can more particularly be between I and 5 mols, and preferably between 1 and 2 mols, per dienoxy group present in the dienoxysilane.
The condensation of the ortho-formate with the dienoxysilane can be carried out either in an organic solvent which is inert towards the reactants used, or in the absence of any solvent. In the first case, the following can be employed as solvents: aliphatic hydrocarbons (e.g. hexane or heptane), cycloaliphatic hydrocarbons (e.g.
cyclohexane), aromatic hydrocarbons (e.g. benzene), ethers (e.g. ethyl ether or
tetrahydrofuran), halogenated hydrocarbons (e.g. methylene chloride, chloroform or carbon tetrachloride), nitriles (e.g. acetonitrile or propionitrile), or carboxamides (e.g. dimethylformamide, dimethylacetamide or N-methylpyrrolidone).
The temperature at which the reaction is carried out can vary within wide limits, depending upon the reactants employed and on the nature and amount of the catalyst. In general, the reaction is carried out at between -40 and +50"C, and preferably between 0 and +100"C. A temperature of between +10 and'+700C is very suitable. However, it is possible to carry out the reaction outside these limits.
The pressure can be equal to, less than or greater than atmospheric pressure: for example, it is possible to work in a closed vessel at the autogenous pressure of the reactants.
As Lewis acids which can be used as catalysts, there may be mentioned boron halides and their complexes with ethers, and transition metal halides (metals of groups lb to 7b and 8 of the periodic classification of the elements: Handbook of
Chemistry and Physics, 53rd edition, published by The Chemical Rubber Co.) Zinc halides and tin halides are particularly suitable and are preferably used. Thus, zinc chloride and bromide and stannous and stannic chlorides and bromides may be used.
The amount of catalyst, expressed as the number of mols of Lewis acid per dienoxy group present in the dienoxysilane, can vary within wide limits. In general, from lx 10-4 to 0.5 mol of Lewis acid, and particularly of zinc or tin halide, per dienoxy group is sufficient to carry out the reaction successfully. This amount is preferably between 1x10-3 mol and 0.2 mol per dienoxy group.
The duration of the reaction depends on the conditions chosen and on the nature of the reactants, and it can vary between a few minutes and several hours.
The present invention further provides, as new products, the ,y-ethylenic b- oxoacetals of the formula:
in which each of R2 to R5, which are identical or different, is hydrogen or alkyl of I to 4 carbon atoms, and R is as hereinbefore defined, provided that when R2 to R5 are identical and represent hydrogen, R is not methyl, and when R2 is methyl, and
R3 to R5 are identical and represent hydrogen, R is not ethyl. Especially valuable are the compounds of formula IV in which R is alkyl of I to 4 carbon atoms, R2 is methyl, and R2, R4 and R5 are each hydrogen.
5*5 - Dimethoxy - 3 - methylpenten - 2 - al, 5,5 - dimethoxy - 2 methylpenten - 2 - al, 5,5 - diethoxy - 3 - methylpenten - 2 - al and 5,5 dimethoxy - 3,4 - dimethylpenten - 2 - al may be mentioned as examples of ethylenic a - oxoacetals of the formula (IV).
These compounds are valuable intermediates in organic synthesis. They make it possible to obtain ethylenic dialdehydes which can be converted, by hydrogenation, into the corresponding pentane glycols which are used for the preparation of various polycondensates such as polyurethanes and polyesters (compare U.S. Patent 3,894,115). When reacted with alkyl ortho-formates in the presence of an acid catalyst (for example a sulphonic acid), they make it possible to obtain the corresponding bis-acetals which are difunctional compounds and very active in organic synthesis.
The following Examples illustrate the invention.
EXAMPLE 1
22.2 g of ethyl ortho-formate (1.5.10-'mol), 0.37 g of molten zinc chloride (2.76.10-3 mol) and 50 cm3 of anhydrous acetonitrile are introduced, under an atmosphere of argon, into a 250 cm3 three-necked round-bottom flask which is equipped with a means of stirring, a condenser and a dropping funnel. The mixture is stirred, and a solution of 23.4 g of l-trimethylsiloxy-3-methyl-l,3-butadiene (1.5.10-' mol) in 15 cm3 of dry acetonitrile is run in over the course of 5 minutes.
The mixture is heated. Reflux is established at 76"C. After heating for 45 minutes, the mixture is cooled to 500C and distilled under pressure of 20 mm of mercy, while the uncondensed volatile products formed and the solvent are collected in a trap.
10.9 g of trimethylsiloxyethane, in the distillate and the trap, are determined and identified by vapour phase chromatography.
The residue is dissolved in 50 cm3 of diethyl ether and neutralised with 25 cm3 of a saturated aqueous solution of sodium bicarbonate. The ether phases are separated, washed with 25 cm3 of distilled water, and dried over potassium carbonate. After distilling off the solvents, 19 g of 5,5-diethoxy-3-methylpenten-2al, in a fraction which passes over at between 75 and 80"C under a pressure of 0.3 mm of mercury, are determined and identified by infra-red spectrometry, vapour phase chromatography and nuclear magnetic resonance.
After rectification, the 5,5 - diethoxy - 3 - methylpenten - 2 - al is in the form of a pale yellow liquid which boils at 730C under a pressure of 0.2 mm of mercury and has a refractive index nD20=1.4602.
The infra-red spectrum of this product, which principally consists of the transisomer and a small amount of the cis-isomer, exhibit the following characteristic bands:
at 1,6701,660 cm-' -C=C- at 1,630 cm-', and -C-O-C- at 1,100 and 1,050cm-' EXAMPLE 2
3.7 g of ethyl ortho-formate (2.5.10-2 mol), 3.9 g of I - trimethylsiloxy - 3 methyl - 1,3 - butadiene (2.5.10-2 mol) and 10 cm3 of methylene chloride are introduced, under a stream of argon, into a 50 cm3 three-necked round-bottomed flask which is equipped with a means of stirring, a condenser and a dropping funnel. 8 mg of stannic chloride (3.10-5 mol) are added rapidly using a syringe. The mixture is stirred and kept at 25"C for 5 minutes. The reaction mixture is neutralised with 25 cm3 of a saturated solution of sodium bicarbonate. 25 cm3 of diethvl ether are added, and the organic phase is then separated, washed with 25 cm3 of a saturated aqueous solution of sodium chloride, and dried over potassium carbonate.
After filtering off the potassium carbonate and removing the solvents under a pressure of 20 mm of mercury, the residue is distilled and a fraction of 2.1 g, which passes over at between 70 and 90"C under pressure of 0.3 mm of mercury, is obtained. In this fraction, 9lv of 5,5 - diethoxy - 3 - methylpenten - 2 - al is determined by vapour phase chromatography.
EXAMPLE 3
13.25 g of methyl ortho-formate (1.25.10-' mol), 0.312 g of zinc chloride (2.3.10-2 mol) and 40 cm3 of anhydrous acetonitrile are introduced, under an atmosphere of argon, into a 250 cm3 three-necked round-bottomed flask equipped with a means of stirring, a condenser and a dropping funnel. A solution of 19.5 g of
1 - trimethylsilyloxy - 3 - methyl - 1,3 - butadiene (1.25.10-' mol) in 15 cm3 of anhydrous acetonitrile is added to the mixture over the course of 5 minutes, while stirring.
The mixture is heated to reflux temperature; after 1 hour 10 minutes, thin layer chromatography is used to check that all the 1 - trimethylsilyloxy - 3 - methyl 1,3 - butadiene has disappeared. The reaction mixture is cooled, and the acetronitrile is driven off under reduced pressure (20 mm of mercury). The residue is neutralised by adding 50 cm3 of a saturated aqueous solution of sodium bicarbonate, and 25 cm3 of diethyl ether are then added. The ether phase is separated, dried over potassium carbonate and then concentrated. By distilling the residue, 12.7 g of 5,5 - dimethoxy - 3 - methylpenten - 2 - al, boiling point 70- 75"C/0.4 mm. Hg. are obtained. The compound is' identified by gas-liquid chromatography and NMR.
WHAT WE CLAIM IS:
1. Process for the preparation of a P,v-ethylenic boxoacetal, which comprises reacting an ortho-formate ester of an alkanol, in the presence of a Lewis acid, with a 1,3-dienoxysilane of the formula:
in which R1, R2, R3, R4,and R,, which are identical or different, are each hydrogen or a hydrocarbon radical, R6 is a hydrocarbon radical, and n is an integer from I to 3.
2. Process according to claim 1, in which the said ortho-formate ester is an ester of the formula: H-C(OR)2 (tri) in which R is straight or branched alkyl of 1 to 4 carbon atoms.
3. Process according to claim 1 or 2, in which in the formula (I), each of R, to R5 represents a straight or branched alkyl of from I to 20 carbon atoms, a straight or branched alkenyl of 2 to 20 carbon atoms, R2 not containing any ethylenic double bond conjugated with the enolic double bond, and R4 and R5 not containing any ethylenic double bond conjugated with that of the carbon to which they are attached, cyclohexyl, cyclopentyl, or phenyl and R6 is alkyl of 1 to 4 carbon atoms, cycloalkyl phenyl or arylalkyl.
4. Process according to claim 1 or 2, in which in the formula (I), each of R1 to R5 represents hydrogen or alkyl of 1 to 4 carbon atoms, n is 3, and R6 is methyl, ethyl or phenyl radical.
**WARNING** end of DESC field may overlap start of CLMS **.
Claims (19)
1. Process for the preparation of a P,v-ethylenic boxoacetal, which comprises reacting an ortho-formate ester of an alkanol, in the presence of a Lewis acid, with a 1,3-dienoxysilane of the formula:
in which R1, R2, R3, R4,and R,, which are identical or different, are each hydrogen or a hydrocarbon radical, R6 is a hydrocarbon radical, and n is an integer from I to 3.
2. Process according to claim 1, in which the said ortho-formate ester is an ester of the formula: H-C(OR)2 (tri) in which R is straight or branched alkyl of 1 to 4 carbon atoms.
3. Process according to claim 1 or 2, in which in the formula (I), each of R, to R5 represents a straight or branched alkyl of from I to 20 carbon atoms, a straight or branched alkenyl of 2 to 20 carbon atoms, R2 not containing any ethylenic double bond conjugated with the enolic double bond, and R4 and R5 not containing any ethylenic double bond conjugated with that of the carbon to which they are attached, cyclohexyl, cyclopentyl, or phenyl and R6 is alkyl of 1 to 4 carbon atoms, cycloalkyl phenyl or arylalkyl.
4. Process according to claim 1 or 2, in which in the formula (I), each of R1 to R5 represents hydrogen or alkyl of 1 to 4 carbon atoms, n is 3, and R6 is methyl, ethyl or phenyl radical.
5. Process according to claim 2, in which R is methyl or ethyl. R1, R2 and R3
are each hydrogen, one of R4 and R5 is hydrogen and the other is hydrogen or methyl, R6 is methyl or ethyl, and n is 3.
6. Process according to any one of claims I to 5, in which the Lewis acid used as the catalyst is a transition metal halide.
7. Process according to claim 6, in which the catalyst used is a zinc or tin halide.
8. Process according to any one of claims 1 to 7, in which the amount of catalyst, expressed in mols per dienoxy group present in the dienoxysilane, is between lx10-4 and 0.5.
9. Process according to any one of claims I to 8, in which the amount of orthoformate, expressed in mols per dienoxy group, is between I and 5.
10. Process according to any one of claims 1 to 9, in which the temperature of the reaction is between -40 and +150 C.
11. Process according to any one of claims I to 10, in which the reaction is carried out in the presence of an inert solvent.
12. Process according to claim 11, in which the solvent used is a chlorinecontaining saturated aliphatic hydrocarbon or a nitrile.
13. Process according to claim 1 for the preparation of a 5,5-dialkoxy-3methylpenten-2-al, which comprises reacting an alkyl ortho-formate in the presence of zinc chloride or tin chloride, with l-trimethylsilyloxy-3-methyl-l-,3- butadiene.
14. ,B,y-Ethylenic b-oxoacetals of the formula:
in which each of R2 to R5, which are identical or different, is hydrogen or alkyl of 1 to 4 carbon atoms, and R is alkyl of 1 to 4 carbon atoms provided that, when R2 to are identical and represent hydrogen R is not methyl, and when R2 is methyl, and
R3 to R5 are identical and represent hydrogen, R is not ethyl.
15. A 5,5-dialkoxy-3-methylpenten-2-al.
16. 5,5-Diethoxy-3-methylpenten-2-al.
17. 5,5-Dimethoxy-3-methylpenten-2-al.
18. Process according to claim I substantially as described in any one of
Examples 1 to 3.
19. A compound as claimed in any of claims 14 to 17 when prepared by a process claimed in any of claims 1 to 13 or 18.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR7715070A FR2391181A1 (en) | 1977-05-17 | 1977-05-17 | PROCESS FOR PREPARING D-OXOACETALS |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1591968A true GB1591968A (en) | 1981-07-01 |
Family
ID=9190911
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB19655/78A Expired GB1591968A (en) | 1977-05-17 | 1978-05-15 | Process for the preparation of 8-oxoacetals |
Country Status (12)
| Country | Link |
|---|---|
| JP (1) | JPS53141204A (en) |
| BE (1) | BE867127A (en) |
| CA (1) | CA1108646A (en) |
| CH (1) | CH633246A5 (en) |
| DD (1) | DD135481A5 (en) |
| DE (1) | DE2821540A1 (en) |
| FR (1) | FR2391181A1 (en) |
| GB (1) | GB1591968A (en) |
| HU (1) | HU179295B (en) |
| IT (1) | IT1096298B (en) |
| NL (1) | NL188634C (en) |
| SU (1) | SU869553A3 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2654105A1 (en) * | 1989-11-09 | 1991-05-10 | Univ Rouen | NOVEL DIENOXYSILANES, PROCESS FOR OBTAINING THEM, AND NOVEL ALPHA-HALOGENATED ALPHA-ETHYLENE ALDEHYDES TO WHICH THEY GIVE ACCESS. |
-
1977
- 1977-05-17 FR FR7715070A patent/FR2391181A1/en active Granted
-
1978
- 1978-05-09 NL NLAANVRAGE7804965,A patent/NL188634C/en not_active IP Right Cessation
- 1978-05-15 JP JP5672078A patent/JPS53141204A/en active Granted
- 1978-05-15 GB GB19655/78A patent/GB1591968A/en not_active Expired
- 1978-05-16 HU HU78RO980A patent/HU179295B/en not_active IP Right Cessation
- 1978-05-16 CA CA303,499A patent/CA1108646A/en not_active Expired
- 1978-05-16 CH CH529178A patent/CH633246A5/en not_active IP Right Cessation
- 1978-05-16 DD DD78205394A patent/DD135481A5/en unknown
- 1978-05-16 BE BE187743A patent/BE867127A/en not_active IP Right Cessation
- 1978-05-17 DE DE19782821540 patent/DE2821540A1/en active Granted
- 1978-05-17 IT IT23510/78A patent/IT1096298B/en active
- 1978-05-17 SU SU782615802A patent/SU869553A3/en active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2654105A1 (en) * | 1989-11-09 | 1991-05-10 | Univ Rouen | NOVEL DIENOXYSILANES, PROCESS FOR OBTAINING THEM, AND NOVEL ALPHA-HALOGENATED ALPHA-ETHYLENE ALDEHYDES TO WHICH THEY GIVE ACCESS. |
| EP0428460A1 (en) * | 1989-11-09 | 1991-05-22 | Universite De Rouen | Dienoxysilanes, methods for their preparation and alpha-ethylenic alpha-halo-aldehydes accessible therefrom |
Also Published As
| Publication number | Publication date |
|---|---|
| BE867127A (en) | 1978-11-16 |
| SU869553A3 (en) | 1981-09-30 |
| DD135481A5 (en) | 1979-05-09 |
| JPS53141204A (en) | 1978-12-08 |
| IT1096298B (en) | 1985-08-26 |
| NL188634C (en) | 1992-08-17 |
| DE2821540A1 (en) | 1978-11-23 |
| JPS6159298B2 (en) | 1986-12-16 |
| NL7804965A (en) | 1978-11-21 |
| CH633246A5 (en) | 1982-11-30 |
| FR2391181B1 (en) | 1981-01-09 |
| CA1108646A (en) | 1981-09-08 |
| FR2391181A1 (en) | 1978-12-15 |
| DE2821540C2 (en) | 1988-02-18 |
| NL188634B (en) | 1992-03-16 |
| HU179295B (en) | 1982-09-28 |
| IT7823510A0 (en) | 1978-05-17 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PS | Patent sealed [section 19, patents act 1949] | ||
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19950515 |