calcination of the Sn–W hydroxide at 800 °C acts as an effective and reusable solid catalyst for CCbond‐formingreactions, such as the cyclization of citronellal, the Diels–Alder reaction, and the cyanosilylation of carbonyl compounds with trimethylsilyl cyanide (see scheme). The observed catalysis was truly heterogeneous, and the recovered catalyst could be reused without loss of its high catalytic performance
METHYL MENTHOL DERIVATIVE AND COOLING AGENT COMPOSITION CONTAINING SAME
申请人:TAKASAGO INTERNATIONAL CORPORATION
公开号:US20180057447A1
公开(公告)日:2018-03-01
The purpose of the present invention is to provide a cooling agent composition containing a novel methyl menthol derivative having no undesirable feeling of stimulation, malodor, bitterness, or the like, it being possible to use the cooling agent composition as a cooling agent or sensory stimulation agent having exceptional persistence of a sense of coolness and refreshing feeling. The present invention pertains to a cooling agent composition containing a methyl menthol derivative represented by general formula (1A) or general formula (1B).
Metal cation-exchanged montmorillonite (M
n+
-mont)
works in acetonitrile at 80 °C as a Lewis acid catalyst for
the intermolecular carbonyl-ene reaction of
α-methylstyrenes with paraformaldehyde to give the
corresponding homoallylic alcohols, Zr
4+
-mont being the most
effective of the many M
n+
-mont catalysts examined.
Similarly, the catalyst is also useful for the highly stereoselective
intramolecular cyclization of citronellals to afford isopulegols, the
reaction being much faster. Regeneration of the catalyst is confirmed
for Zr
4+
-mont, which can be effectively recycled at least
five times.
metal-free catalytic system composed of trityl halides and thioureas has been found to be a convenient source for the generation of trityl cation species, and this cooperative catalytic system was proved to be highly effective for intramolecular carbonyl-ene cyclization and [2+2] cycloadditions.
A lactone compound is represented by general formula (A), and an ether compound is represented by general formula (B). In formula (A), R is a hydrogen atom or R1. When R is a hydrogen atom, R′ is R1, the carbon bond (1) is a single bond or a double bond, and the carbon bond (2) is a single bond. When R is R1, R′ is a hydrogen atom or R1, both the carbon bonds (1) and (2) are a single bond, or one of them is a double bond and the other is a single bond. In formula (B), R″ is R1. R1 represents a specific alkyl group, a specific alkenyl group, a specific alkynyl group, or an aryl group. In formulas (A) and (B), n is 0 or 1.