ISSN:1042-7163    

DOI:10.1002/hc.520030502

出版商:VCH Publishers, Inc.    

年代:1992

数据来源: WILEY

摘要:

AbstractBy the reaction of [(μ‐RS (μ‐CO)Fe2(CO)6] [Et3NH] with MeAsI2, six new double cluster complexes, [(μ‐RS) (μ‐MeAs)Fe2(CO)6]2(R = Et, Pr,iPr, Bu, C5H11, Ph), were synthesized. The structure of theiPr analog was determined by single crystal X‐ray diffraction techniques. Crystal data were as follows: monoclinic, P21/n, Z = 4, a = 14.475(4), b = 13.825(3), c = 17.225(5) Å, β = 112.44(2)°, V = 3186 Å3, R = 0.0

ISSN:1042-7163    

DOI:10.1002/hc.520030503

出版商:VCH Publishers, Inc.    

年代:1992

数据来源: WILEY

摘要:

AbstractThe reaction of 2,2‐disubstituted 1,3‐cyclohexane‐diones(1) with dimethyl methylphosphonate anion in the presence of trimethylsilyl chloride produces 3‐substituted 2‐cyclohexenones (2) in moderate to very good yields. This new overall reaction is accounted for by (1) attack of the phosphonate anion on a carbonyl group, (2) retro‐aldol cleavage, (3) reorganization of the acidic proton, and (4) an intramolecular Wadsworth‐Emmonds condensation. The new rearrangement is applied to a short synthesis of (±)‐α‐acoradiene. The synthesis of 3‐sub‐stituted 2‐cyclopentenones (10) is accomplish

ISSN:1042-7163    

DOI:10.1002/hc.520030504

出版商:VCH Publishers, Inc.    

年代:1992

数据来源: WILEY

摘要:

AbstractThe reactions of 3‐sulfolenes with PhSCl under basic‐conditions produce phenyl 1,3‐butadienethiosulfonates7a–din low yields without the formation of 2‐sulfenylated 3‐sulfolenes8. Compounds7a–dcan be prepared in high yields from 3‐sulfolenes by the sequence of deprotonation, anionic cycloreversion, and phenylsulfenyl

ISSN:1042-7163    

DOI:10.1002/hc.520030505

出版商:VCH Publishers, Inc.    

年代:1992

数据来源: WILEY

摘要:

AbstractA variety of 3‐alkynyl perfluoroalkyl ketones were prepared by a trifluoroborane etherate mediated 1,4‐addition reaction of (l‐alkynyl)diisopropoxyboranes to α,β‐unsaturated ketones substituted by a perfluoroalkyl group. The undesired side reaction, such as 1,2‐addition of alkynyl groups, could be avoided completely and the products were obtained in

ISSN:1042-7163    

DOI:10.1002/hc.520030506

出版商:VCH Publishers, Inc.    

年代:1992

数据来源: WILEY

摘要:

AbstractHeterocyclic ketene aminals reacted with aryl isothiocyanates to give products of addition to the β‐carbon. By oxidative cyclization of these addition products by the action of bromine, isothiazole‐fused heterocycles or benzothiazole‐substituted heterocyclic ketene aminals were formed according to the influence of the different substi

ISSN:1042-7163    

DOI:10.1002/hc.520030507

出版商:VCH Publishers, Inc.    

年代:1992

数据来源: WILEY

摘要:

AbstractNew stable sulfenate salts,sodium 2‐pyridinesulfenate9aand sodium 2‐(3‐trimethylsilyl)pyridinesulfenate9b, were prepared by the ipso‐substitution reactions of azaheterocyclic sulfoxides (1c/3aand4a, respectively) with sodium ethoxide or sodium butanethiolate under mild conditions and were characterized by physical and spectroscopic properties. The FT‐IR spectra of compounds9aand9bshowed characteristic SO absorptions at 870 and 890 cm−1, respectively. These sulfenate salts were converted rapidly to the corresponding sulfinate salts on contact with oxygen. A number of other sulfenates were prepared and trapped by alkylation to give sulfoxides (as

ISSN:1042-7163    

DOI:10.1002/hc.520030508

出版商:VCH Publishers, Inc.    

年代:1992

数据来源: WILEY

摘要:

AbstractReactions of 2‐aryl‐1,3‐dithiolane‐S‐oxides1with MeMgl in refluxing benzene‐ether furnish a useful procedure for introducing the isopropenyl group. The reaction may proceed via a fragmentation‐coupling process leading to the alkylative olefin

ISSN:1042-7163    

DOI:10.1002/hc.520030509

出版商:VCH Publishers, Inc.    

年代:1992

数据来源: WILEY

摘要:

AbstractFunctionalized cyclopropyl ketones have been found to undergo facile reductive cyclopropane ring opening with samarium (II) diiodide in the presence of a proton source. These reactions were exceedingly rapid, taking place in most cases at −78°C under neutral conditions. An ester group substituted at the C2position of the cyclopropane ring played an important role in the ring opening of cyclopropyl keton

ISSN:1042-7163    

DOI:10.1002/hc.520030510

出版商:VCH Publishers, Inc.    

年代:1992

数据来源: WILEY

摘要:

AbstractThe stereochemistry of the α‐sulfinyl carbanion has been studied. It has been elucidated that a 2‐pyridylmethyl substituent on the sulfinyl sulfur chelates onto the counter cation in an ion pair to fix the conformation of the anion at a particular orientation. Then, the steric bulk of the other substituent plays a role to control the reacting face. A soft electrophile such as methyl iodide attacks the anion from the more open side. On the other hand, a hard electrophile such as a proton is initially trapped by the polar part of the ion pair and no steric effect oper

ISSN:1042-7163    

DOI:10.1002/hc.520030511

出版商:VCH Publishers, Inc.    

年代:1992

数据来源: WILEY