Page 27 - Academic Press Encyclopedia of Physical Science and Technology 3rd Organic Chemistry

P1: GLQ Final Pages
Encyclopedia of Physical Science and Technology EN001F-4 May 30, 2001 12:13

Acetylene 79

B. Kerb
HCl NH 3
(CH 3 ) 2 C C CH (CH 3 ) 2 C C CH (CH 3 ) 2 C C CH
OH Cl NH 2

Cl
CH 3
Base
CONH C C CH
Cl
CH 3
Cl COCl
Kerb
Cl
C. Omite

OH
NaOH O
(CH 3 ) 3 C OH O (CH 3 ) 3 C
catalyst

SOCl 2
C 5 H 5 N

OSOCl
O
C CH C
OSO 2 CH 2 (CH 3 ) 3
OC CH 2 C CH
O
(CH 3 ) 3 C
omite

XIII. ACETYLENIC REACTIONS WITH A. Cyclic Carbonates from Alkynol–
RESEARCH AND COMMERCIAL Alkynediol–Carbon Dioxide Reactions
POTENTIAL An interesting reaction discovered by Dimroth and
Pasedach at BASF involves the reaction of tertiary
The products and reactions described in this section acetylenic alchols and diols with carbon dioxide under
have not been extensively developed on a commercial pressure to form substituted cyclic carbonates (5-methy-
scale but are believed to have potential in fine-chemicals lene-4,4-di-alkyldioxolan-2-ones). The reaction is cat-
applications. alyzed by the combination of a cuprous salt and a tertiary
←−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
FIGURE 12 Vitamin E: reaction sequence leading to isophytol.
Abbreviation Common name Process step and reaction
MB Methylbutynol (0) Ethynylation of acetone
MBe Methylbutenol (1) Semihydrogenation (Pd)
DMAAA Dimethylallyl acetoacetate (2) Diketene (DK), ketenization
MH Methylheptenone (3) Allylic isomerization (Carrol)
DHL Dehydrolinalool (4) Ethynylation of MH
L Linalool (5) Same as (1)
GA Geranylacetone (6) Same as (2) and (3)
DHN Dehydronerolidiol (7) Same as (4)
N Nerolidol (8) Same as (1) and (5)
FA Farnesylacetone (9) Same as (2), (3), and (6)
HHFA Hexahydrofarnesylacetone (10) Complete hydrogenation, side chain
IP Isophytol (11) Same as (4) and (5)