The direct synthesis of conjugated dienes from alkynes is highly desirable for forming valuable synthetic intermediates."] A number of methods are available for the stereoselective preparation of dienes from acetylenes,I2] but these either rely on the use of a stoichiometric amount of a reactive organometallic species (precluding the presence of sensitive substituents) ,131 require more than one reaction step,[41 or start from pure stereoisomers of alkenyl compounds in cross-coupling reactions.[51 A high-yield. selective catalytic procedure for preparing conjugated "open-chain'' dienes directly from acetylenes has not been described .I6] As part of our continuing studies on carbon-carbon and carbon-heteroatom cross-coupling mediated by palladium compounds with ancillary, rigid, bidentate nitrogen ligands (Scheme I ) , instead of the usual phosphanes, we re- Ar-bianPh-bip Scheme 1. Bidentate N ligands. port a new catalytic three-component synthesis of conjugated dienes by coupling of alkynes with an organic halide and tetramethyltin. Mechanistic details have been elucidated that reveal that stereospecific oxidative addition and reductive elimination at carbopalladacyclic compounds occurs, and that intermediate Pd', Pd", and Pd" species are involved in the catalytic cycle. Palladacycles l[*l react with one equivalent of an organic halide (for example benzyl bromide, methyl iodide, or iodobenzene) in dichloromethane at 20 "C to give dienyl(NN-K2-N,N)palladium(Ir) halides ZC9l (Scheme 2; NN = bis (aryl-im1no)acenaphthene (Ar-bian), bis(pheny1imino)phenanthrene (Ph-bip),["] or 2,2'-bipyridine (bpy)). Compounds 2 are formed by a sequence of oxidative addition and reductive elimination at palladium via triorgano(NN-tc2N,N)palladium(Iv) halides 1743 1; E = COZCH~ RX = C6H5CH,Br, CH31, C, &I NN = Ar-bian, Ph-bip, bpy A 1 2a; R = C6H5CH2; X = Br 2b; R =CH3; X = I 2 C ; R =C6H5; x = I Scheme 2. Stoichiometric reaction of palladacyclopentadienes 1 with organic halides and Me,Sn. [a] With addition of Br, (instead of Me,Sn) to 2b in CH,CI, directly after its formation. A,["]Reaction of 2a-c with tetramethyltin in DMF at 60-85 "C leads to the selective formation of 2,5-difunctionalized 2,4-hexadienoates 3a-c. Sequential addition of methyl iodide and one equivalent of Br, to 1 in dichloromethane results in the 2-bromo-5-methyl derivative 3x.Since formation of palladacycles 1 from [Pd(dba),] (dba = dibenzylideneacetone) and electron-poor alkynes is much faster than oxidative addition of benzyl bromide to zero-valent Pd species, and insertion of a third molecule of acetylene in 1 is slower than reaction of the organic halide with 1 to give 2, we anticipated that a catalytic procedure for the synthesis of dienes 3 (Scheme 3), consisting of the single steps shown above, was feasible. Indeed, employing 1 as the precatalyst (or [Pd(dba),]and an equimolar amount of Ar-bian or Ph-bip) with I +

This study was designed, first, to identify the existence of distinct personality types among a large sample of alcoholic psychiatric patients, and second, to relate this empirically derived taxonomy to types from previous research with alcoholic patients and to general psychiatric types. Employing a sequential factor-analytic strategy, eight bipolar typal dimensions that defined one cluster of persons at each pole of each dimension were identified. The five clearest bipolar typal dimensions were classified as follows: 1, acute anxiety versus denial and blunted affect; 2, antisocial attitudes versus hypochondriacal preoccupation; 3, hostile-hallucinatory syndrome versus neurotic depression; 4, neurotic disorganization versus hostile paranoid; 5, emotional instability versus interpersonal conflict and depression. Minnesota Multiphasic Personality Inventory (MMPI) profiles from prior research with a variety of psychiatric groups showed marked correspondence with MMPI profiles estimated for the eight common types.

The Minnesota Multiphasic Inventory (MMPI) scores of 32 college freshman males later hospitalized as alcoholics were compared with scores of 148 male classmates for clinical, content scale, and item differences. The prealcoholics were significantly higher on Scales F, 4 (Psychopathic Deviate), and 9 (Hypomania). The investigators concluded that the college prealcoholic is more likely to be impulsive, nonconforming, and gregarious but is otherwise not grossly maladjusted compared to his peers.

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