From val[ AT ]nmr1.ioc.ac.ru Tue Feb 25 09:25:41 1997 Received: from nmr1.ioc.ac.ru for val -8 at 8- nmr1.ioc.ac.ru by www.ccl.net (8.8.3/950822.1) id IAA22834; Tue, 25 Feb 1997 08:32:46 -0500 (EST) Received: from [193.233.3.213] (nmr-v.ioc.ac.ru [193.233.3.213]) by nmr1.ioc.ac.ru (8.6.12/8.6.9) with SMTP id QAA03720 for ; Tue, 25 Feb 1997 16:32:45 +0300 Date: Mon, 24 Feb 97 16:32:41 +0300 From: "Ananikov V.P." Message-Id: <70889.val: at :nmr1.ioc.ac.ru> X-Minuet-Version: Minuet1.0_Beta_17A Reply-To: X-POPMail-Charset: IBM 8-Bit To: CHEMISTRY ^%at%^ www.ccl.net Subject: cations binding to the acetilenic compounds Dear All, I am trying to study out the difference(bond energy, geometry, etc.) in binding of various cations to the carbon-carbon triple bond. Especially I am interesting in the following sequence: -C tr.bond C- + H(+) = .... proton binding to the triple bond -C tr.bond C- + Hal(+) = ... halogen cations binding -C tr.bond C- + Me = .... transition metal complex binding According to the literature the interaction between halogen cations and C=C double bond leads to the formation of three intermediates: + + -C=C- + X(+) = -C-C- -C-C- X-C-C- | \+/ | X X (I) (II) (III) where (III) and (II) are nearly equal in energy but (I) has a high energy and it is assuming to be very unstable. Does anyone have an information concerning the stability of cyclic and acyclic cations formed from the acetylenic compounds? I appreciate receiving any references about theoretical investigations of cation interactions with C-C triple bond. I will summarize. Thank you in advance. Valentin. Valentin P. Ananikov NMR Laboratory N.D. Zelinsky Institute of Organic Chemistry Leninsky Prospect 47 Moscow 117913 Russia e-mail: val -8 at 8- nmr1.ioc.ac.ru Fax (095) 135 5328 Phone (095) 135 9094, (095) 938 3536