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A highly efficient strategy is developed for the rapid asymmetric synthesis of gem-dimethyl and spirocyclopropyl norbornyl carboxylic acids. The key transformation involved the unprecedented asymmetric Diels-Alder reaction of highly reaction beta,beta-cyclopropyl-alpha,beta-unsaturated N-acyloxazolidinoones with cyclopentadiene affording the adducts in high yield and de.

A general asymmetric synthesis of substituted cycloalkyl[b]indoles is accomplished. The use of trimethylphosphine (PMe3) and bis(2,2,2-trichloroethyl) azodicarboxylate (TCEAD) is found to have an effect on the Mitsunobu dehydrative alkylation.

The title complex, [ZrCl2(C4H8O)2(C14H14N)2]·0.5C7H8, was prepared in an unusual manner by utilizing [Mg{N(CH2Ph)2}2] as a ligand transfer reagent. The Zr atom lies in a distorted octahedral environment where steric repulsion from the large di­benzyl­amino ligands leads to a widening of the N-Zr-N angle [99.95 (9)°] and corresponding compression of other angles [Cl-Zr-Cl 160.95 (3)° and O-Zr-O 78.22 (7)°]. This distortion is compared with those found in the previously determined structures of the di­methyl­amino and diethyl­amino analogues. [ABSTRACT FROM AUTHOR]

A general asymmetric synthesis of substituted cycloalkyl[b]indoles has been accomplished. The key features of this approach are (1) the utilization of a Japp-Klingemann condensation/Fischer cyclization to prepare cycloalkyl[b]indolones, (2) the asymmetric borane reduction of these heterocyclic ketones with (S)-OAB to obtain enantiomerically pure alcohols, and (3) the stereoselective S(N)2-displacement of these indole alcohol substrates with a carbon nucleophile under Mitsunobu conditions to set the C1 or C3 tertiary carbon stereocenter. The use of trimethylphosphine (PMe3) and bis(2,2,2-trichloroethyl) azodicarboxylate (TCEAD) was found to have an effect on the Mitsunobu dehydrative alkylation.