We report the first GNO solar neutrino results for the measuring period GNO I, solar exposure time May 20, 1998 till January 12, 2000. In the present analysis, counting results for solar runs SR1–SR19 were used till April 4, 2000. With counting completed for all but the last 3 runs (SR17–SR19), the GNO I result is [65.8 ± 10.29.6 (stat.) ± 3.43.6 (syst.)] SNU (1σ) or [65.8 ± 10.710.2 (incl. syst.)] SNU (1σ) with errors combined. This may be compared to the result for Gallex (I–IV), which is [77.5 ± 7.67.8 (incl. syst.)] SNU (1σ). A combined result from both GNO I and Gallex (I–IV) together is [74.1 ± 6.76.8 (incl. syst.)] SNU (1σ)

Various aqueous surfactants proved to be excellent media for carrying out palladium-catalyzed Suzuki−Miyaura cross-coupling reactions under mild conditions. The dehalogenation side reaction, which is usually a drawback with the aqueous protocol, was not observed. The concentration of the surfactant in water played a pivotal role for the reaction outcome. Smooth cross-coupling of iodoanisole and a variety of aryl bromides, including electron-rich derivatives, with aryl boronic acids occurred at room temperature in high yields either with [Pd(PPh3)4] or Pd/C as catalyst. The water-surfactant Pd/C system combines high activity under ambient conditions (air), easy separation and recyclability. Palladium acetate was found to be effective in cross-coupling of the less reactive aryl chlorides at 100 °C

The and 13C chemical shifts of methyl naphthalene-2-sulfonate and naphthalene-2-sulfonate anion show that these compounds are located at the micellar interface in aqueous cetyltrialkylammonium bromides (alkyl = Me, Et, n-Pr, n-Bu). Increase of the surfactant headgroup size moves the ester closer to the cationic center. Reaction with Br" is faster and there is a more favorable interaction of the naphthalene -system with the positive center. Micellar incorporation of Br" markedly

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Aqueous cationic micelles of R'NR3Br (R' = C12H25, R = Me, DoTABr; R' = C16H33, R = Me, CTABr; R' = C16H33, R = Bu, CTBABr) and R ' N M~~( C H Z ) W~~R~B~ ( R = C16H33) increase rates of cyclization of O--OC6&o(CH2)n-~ (X = Br, I) designated PhXn. Rate increases are small, except for Ph17 in CTBABr,l and activation parameters are similar to those in water or 75% aqueous EtOH. In very dilute surfactant there are large rate increases, by factors of up to 39 with PhI16 in CTABr, but CTBABr is less effective. These rate increases are ascribed to formation of substrate-premicellar complexes of PhBrlO, PhBrl2, and PhX16 with all the surfactants. These complexes dissolve into normal micelles at higher [surfactant], and the unusual rate effects disappear.Cyclizations of o-(whaloa1koxy)phenoxide ions, 1 (Scheme 1) are well studied,2 and factors such as ring strain and loss of rotational entropy in formation of the transition state have been explored in detail. Following precedent, we write substrate structure in terms of the size of the ring formed by cyclization.2These cyclizations can be regarded as intramolecular sN2 reactions with varying effective molarities (EM).2 Reactions of the o-(3-bromopropyloxy)phenoxide and 0-(3-iodopropy1oxy)phenoxide (PhBr7 and PhI7, respectively) in aqueous micelles are useful models for micellar effects upon rates of sN2 reactions in the interfacial region at micellar surfaces.' First-order rate constants in this region k", can be compared with those in water, k',, and a t 25.0 "C values of k',/k', range from 1.7 and 3.9 for PhBr7 and Ph17 in CTABr, CH3(CH2)15N(CH3)3Br, to 7.7 and 34 in CTBABr, C H~( C H Z )~~N [ ( C H~)~C H & B~.These relative rate constants decrease modestlywith increasing temperature.3These values of k'm/Kw show that cationic micelles do not significantly control initial state conformations of PhX7 so as to increase rates of cyclization. We were therefore * To whom the correspondence should be addressed. @ Abstract published in Advance ACS Abstracts, September 1, 1994. (1) Cerichelli, G.; Luchetti, L.; Mancini, G.; Muzzioli, M. N.; Germani, R.; Ponti, P. P.; Spreti, N.; Savelli, G.; Bunton, C. A. J. Chem. SOC., Perkin Trans. 2 1989, 1081. (2) (a) Illuminati, G.; Mandolini, L.; Masci, B. J. Am. Chem. SOC. 1974,96,1422. (b) Illuminati, G.; Mandolini, L.; Masci, B. J. Am. Chem. SOC. 1977, 99, 6308. (c) Dalla Cost, A.; Illuminati, G.; Mandolini, L.; Masci, B. J. Chem. SOC., Perkin Trans. 2 1980, 1774. (3) Cerichelli, G.; Luchetti, L.; Mancini, G.; Savelli, G.; Bunton, C. A. J. Colloid Interface Sci. 1993, 160, 85. Scheme 1 1 X = B r , I interested in the report by Wei et al. that, although micelles of CTABr did not significantly assist cyclization of PhBr7, they markedly speeded cyclization of the larger chain homolog^.^ However, rates were measured only at loe3M CTABr, which is very close to the critical micelle concentration, cmc (ca. 8 x M in water at 25 0C),5 so that micelles were in very low concentration. Under these conditions it is necessary to consider the possibi...