Reactions of Nitridorhenium(V) and -Osmium(VI) Complexes with Acylating Agents.

Inorg Chem

Departments of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, and The University of Hong Kong, Pokfulam Road, Hong Kong.

Published: June 1999

Interaction of Re(N)L(2) [L = N(PSPh(2))(2)] 1 with (CF(3)CO)(2)O or RCOCl afforded air-sensitive acylimido-Re(V) complexes trans-Re[NC(O)CF(3)](OCOCF(3))L(2) 2 or trans-Re[NC(O)R]ClL(2) (R = CCl(2)H 3, CClH(2) 4, CH(3) 5), respectively. Treatment of 1 with (CX(3)CO)(2)O followed by recrystallization from CH(2)Cl(2)/hexane in air led to the formation of the corresponding parent imido complexes trans-Re(NH)(OCOCX(3))L(2) (X = F 6, Cl 7). The structure of 7 has been characterized by X-ray crystallography. The Re-N, average Re-S, and Re-O distances are 1.664(3), 2.441, and 2.116(3) Å, respectively. Deprotonation of 6 or 7 with Et(3)N gave 1. Recrystallization of 3 from CH(2)Cl(2)/hexane in air resulted in oxo-imido exchange and the isolation of the oxo-Re(V) species trans-Re(O)ClL(2). Treatment of 1 with tosyl anhydride gave trans-Re(NH)(OTs)L(2) (OTs = tosyl) 8. Reaction of [n-Bu(4)N][OsNCl(4)] with KL afforded trans-Os(N)ClL(2) 9, which has been characterized by X-ray crystallography. The Os-N, Os-Cl, and average Os-S bond distances in 9 are 1.64(1), 2.577(4), and 2.429 Å, respectively. Treatment of 10 with (CF(3)CO)(2)O, Ag(CF(3)CO(2)), or CF(3)CO(2)H resulted in chloride substitution and the formation of trans-Os(N)(OCOCF(3))L(2) 10. The Os-N, Os-O, and average Os-S distances in 10 are 1.643(5), 2.271(4), and 2.419 Å, respectively. Treatment of 1 with [Ph(3)C]BF(4) resulted in the isolation of trans-Re(NCPh(3))(F)L(2) 11, presumably via the cationic tritylimido intermediate [Re(NCPh(3))L(2)](+). Reaction of 9 with [Ph(3)C]BF(4) led to chloride abstraction and the formation of five-coordinate [Os(N)L(2)]BF(4) 12. The Os-N and average Os-S distances in 12 are 1.646(5) and 2.364 Å, respectively.

Download full-text PDF

Source
http://dx.doi.org/10.1021/ic981244bDOI Listing

Publication Analysis

Top Keywords

average os-s
12
recrystallization ch2cl2/hexane
8
ch2cl2/hexane air
8
characterized x-ray
8
x-ray crystallography
8
os-s distances
8
reactions nitridorheniumv
4
nitridorheniumv -osmiumvi
4
-osmiumvi complexes
4
complexes acylating
4

Similar Publications

Purpose: To describe concentration versus time profiles of capecitabine and its metabolites 5'-DFUR, 5'-DFCR and 5-FU, depending on tablet formulation and on frequent and/or relevant genetic polymorphisms of cytidine deaminase, dihydropyrimidine dehydrogenase, thymidylate synthase and methylenetetrahydrofolate reductase (MTHFR).

Methods: In 46 cancer patients on chronic capecitabine treatment, who voluntarily participated in the study, individual therapeutic doses were replaced on four consecutive mornings by the study medication. The appropriate number of 500 mg test (T) or reference (R) capecitabine tablets was given in randomly allocated sequences TRTR or RTRT (replicate design).

View Article and Find Full Text PDF

A double-blind, placebo-controlled trial assessing the efficacy of varenicline tartrate for alcohol dependence.

J Addict Med

April 2014

From the Division of Treatment and Recovery Research (RZL, MLR, JBF DEF), National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD; Department of Psychiatric Medicine (BJ, NAT), University of Virginia, Charlottesville, VA; Johns Hopkins University School of Medicine (KED, ECS), Baltimore, MD; Geisel School of Medicine at Dartmouth (AIG, MFB), Lebanon, NH; University of Pennsylvania Treatment Research Center (HMP, KK), Philadelphia, PA; Boston University School of Medicine (DAC, OS-S), Boston, MA; Fast Track Drugs and Biologics (JR, CS), North Potomac, MD; and Decision Sciences Institute/Pacific Institute for Research and Evaluation (RS), Pawtucket, RI. NCIG Study Group members are as follows: Boston Medical Center, Boston, MA and Quincy, MA (Joanna Piechniczek-Buczek, MD, Chris Streeter, MD, Eric Devine, PhD, Courtney Richambault, Laurie Sickles-Colaneri, RN); University of Virginia, Charlottesville, VA (Eva Jenkins-Mendoza, Sean Sembrowich, RN, Jennifer Kim Penberthy, PhD, Amanda Nizam, Nicole Fischer, Shari Steinman, Mindy Borszich); University of Virginia, Richmond, VA (Esther Makanjuola, RN, Tricia Schirmer, Kathryn Polak, Christina Hill, Kathryn Conley, Alison Eonta, Kasy Serdar, Aubrey Gartner, Amy Madigan); Geisel School of Medicine at Dartmouth, Hanover, NH and Bedford, NH (Audrey Kern, MD, Christopher O'Keefe, MS, Mirranda Boshart, Suzanne Miller, Shannon Rondeau, RN, Marjorie Weeks, Pamela Geiger); University of Pennsylvania, Treatment Research Center, Philadelphia, PA (Jennifer Plebani, PhD, William Dundon, PhD, Elizabeth Mahoney, MA, Gail Kaempf, CRPN, Brenda Beitler, APRN, Cynthia Clark, CPRN, Kelly Griffin, Joshua Lachewitz, Elizabeth Wilson, Margo Hendrickson, Tamara Roth, Laurie Downing, NP); and Johns Hopkins University School of Medicine (Joseph Harrison, MS, Kimberly Nelson, LPN, Ashley Bathgate, Connie Lowery, RN, Elana Schwartz, Torran Claiborne, Sarah Hersh).

Objectives: To assess the efficacy and safety of varenicline (Chantix) for the treatment of alcohol dependence. Varenicline is a partial α4β2 nicotinic acetylcholine agonist approved by the Food and Drug Administration for smoking cessation. It has reduced drinking in animal studies and in small studies of humans who were both heavy drinkers and smokers.

View Article and Find Full Text PDF

Objective: More than 50% of all fractures occur in people without osteoporosis. Hormone therapy increases bone density, improves postural balance, and reduces fracture risk in postmenopausal women. It is unclear whether tibolone, a synthetic steroid hormone drug, can improve muscle strength.

View Article and Find Full Text PDF

Tibolone low dose (1.25 mg/d) therapy and postural balance in elderly women.

Maturitas

January 2009

Department of Women's and Children's health, Section for Obstetrics & Gynecology, University Hospital, SE-751 85 Uppsala, Sweden.

Unlabelled: Most hip fractures occur in subjects without osteoporosis and are associated with a fall. Conventional menopausal hormone therapy (HT) improves postural balance, which might explain the rapid reduction in hip fracture risk. It is unclear whether tibolone improves postural balance, which might determine its effects on peripheral fracture risk.

View Article and Find Full Text PDF

The influence of skin on the bias and reproducibility of regional cerebral oxygenation measurements is investigated using cw near-infrared spectroscopy (NIRS). Receiving optodes are placed over the left and right hemispheres of a piglet (C3, C4 EEG placement code) and one transmitting optode centrally (Cz position). Optical densities (OD) are measured during stable normo, mild, and deep hypoxemia.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!