From chemistry-request- at -server.ccl.net Wed Aug  1 15:47:11 2001
Received: from hotmail.com ([64.4.37.25])
	by server.ccl.net (8.11.0/8.11.0) with ESMTP id f71JlB507121
	for <chemistry %-% at %-% ccl.net>; Wed, 1 Aug 2001 15:47:11 -0400
Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC;
	 Wed, 1 Aug 2001 12:47:06 -0700
Received: from 66.81.51.229 by pv2fd.pav2.hotmail.msn.com with HTTP;	Wed, 01 Aug 2001 19:47:06 GMT
X-Originating-IP: [66.81.51.229]
From: "Yuan-Yuan chen" <yuan_yuanchen \\at// hotmail.com>
To: chemistry: at :ccl.net
Subject: Pericyclic additions
Date: Wed, 01 Aug 2001 15:47:06 -0400
Mime-Version: 1.0
Content-Type: text/plain; format=flowed
Message-ID: <F25bLAX3cf3ednHM3SO0000b648 #at# hotmail.com>
X-OriginalArrivalTime: 01 Aug 2001 19:47:06.0861 (UTC) FILETIME=[BEB539D0:01C11AC2]

Hi, every one

There are two recent papers of contradictory opinions on the mechanism of 
Diels-Alder reactions if you are interested:

1. Tetrahedron Lett. 2001, 42, 5077. “Merging of 4+2 and 2+4 cycloadditon 
paths in the regiospecific dimerization of methacrolein. A case of concerted 
crypto-diradical cycloaddition”

2. http://preprint.chemweb.com/orgchem/0107002
	“Collision-induced electron reorganization as the general mechanism of 
concerted cycloaddition reactions”.

Yuan-Yuan


_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp