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Organic semiconductors are promising materials for future electronic and electroluminescence applications. A detailed understanding of organic layers and nano-sized crystals down to single molecules can address fundamental questions of contacting organic s ...
Treatment of optically active (PrCHBr)2CH2 with Li-Hg or biphenyl-Li gave 46:54 or 59:51, resp., cis- and trans-1,2-dipropylcyclopropane (I). The original (R,R)-configuration at both chiral centers was inverted in the course of the cyclization reaction lea ...
Increasing awareness that popular functionals fail to describe many energies accurately has ended expectations of black-box DFT usage. The performance of nine d. functionals, compared by computing the bond sepn. energies of 72 illustrative hydrocarbons wit ...
Ring strain confers to the cyclopropane ring an exceptional reactivity. Nevertheless, activation of the cyclopropane ring is usually needed to allow ring-opening reactions under mild conditions. The introduction of one or several carbonyl functionalities o ...
The equil. Br2(g) + 2NO(g) .dblarw. 2BrNO(g) was studied at 275-363 K. Third-law calcns. lead to DH Deg298(1) = -11.50 +- 0.17 kcal/mol, from which DH Degf298(BrNO, g) = 19.52 +- 0.24 kcal/mol and D Deg0(Br-NO) = 27.90 +- 0.30 kcal/mol. Absorption bands of ...
The Nazarov cyclization of divinyl ketones gives access to cyclopentenones. Replacing one of the vinyl groups by a cyclopropane leads to a formal homo-Nazarov process for the synthesis of cyclohexenones. In contrast to the Nazarov reaction, the cyclization ...
Abstract: Activated cyclopropanes, such as vinyl and carbonyl cyclopropanes, are useful building blocks in organic chemistry due to their exceptional reactivity. This review focuses on the use of cyclopropyl carbonyls and imines in cyclization and cycloadd ...
A new catalytic procedure for atom-transfer radical addition (ATRA) and cyclization (ATRC) reactions is described. The combination of the ruthenium(III) complex [RuCl2Cp*(PPh3)] with magnesium allows these reactions to be performed under mild conditions wi ...
The continuous progress in medicinal chemistry requires more versatile synthetic strategies for the generation of large libraries of active compounds and their analogues. As a result, the research for new effective cyclization and cycloaddition reactions i ...
The structural, vibrational, and conformational properties of small perfluoro n-alkanes CnF2n (n ? 5) have been studied with different d. functional models. The relative conformational energies are severely underestimated within the local d. approxn. (LDA) ...
