Instant-Ylid: ein lagerfähiges und gebrauchsfertiges Wittig-Reagenz
Mixts. prepd. from alkyltriphenylphosphonium bromides and powd. NaNH2 were stored indefinitely. Upon addn. of an ethereal solid, however, they immediately generated the ylide, which then reacted with aldehydes, ketones, and formates. The use of such instant ylide mixts. offered distinct advantages over conventional Wittig procedures: optimum yields (even with enolizable ketones), highest cis/trans ratios, largest range of applicability, shortest reaction times, and easiest handling. Thus, condensation of Ph3:CHEt with BzH gave 94% (Z)-PhCH:CHEt and 6% (E)-PhCH:CHEt. Among the approx. 30 compds. prepd. were cis- and trans-stilbenes, methylenecyclohexane, and cis- and trans-BuOCH:CHEt. [on SciFinder (R)]
1982
36
10
396
7
CAN 98:143526
29-7
Organometallic and Organometalloidal Compounds
Inst. Chim. Org.,Univ. Lausanne,Lausanne,Switz.
Journal
written in German.
98-53-3; 100-52-7; 107-31-3; 108-94-1; 110-62-3; 111-71-7; 120-92-3; 123-72-8; 592-84-7 Role: RCT (Reactant), RACT (Reactant or reagent) (condensation of, with storable and ready to use Wittig reagents); 103-30-0P; 627-97-4P; 645-49-8P; 768-49-0P; 1005-64-7P; 1560-09-4P; 4110-75-2P; 4110-77-4P; 4604-28-8P; 5749-72-4P; 7642-18-4P; 14371-19-8P; 15436-06-3P; 16002-93-0P; 16939-57-4P; 19150-21-1P; 19398-86-8P; 20063-92-7P; 20237-46-1P; 22617-94-3P; 22617-95-4P; 31915-94-3P; 35822-50-5P; 39491-64-0P; 39491-65-1P; 40642-40-8P; 53366-50-0P Role: SPN (Synthetic preparation), PREP (Preparation) (prepn. of); 100-42-5P; 111-66-0P; 766-90-5P; 873-66-5P; 1192-37-6P; 6434-77-1P; 6434-78-2P Role: SPN (Synthetic preparation), PREP (Preparation) (prepn. of, by use of storable Wittig reagents); 1754-88-7; 3487-44-3; 3728-50-5; 15935-94-1; 16666-78-7; 16666-80-1; 16721-45-2; 23462-73-9; 29949-92-6; 65734-62-5 Role: RCT (Reactant), RACT (Reactant or reagent) (storability and use of); 19493-09-5; 19493-10-8; 19493-11-9; 20262-13-9; 20262-14-0; 21655-89-0; 29942-59-4; 73671-51-9; 80922-35-6; 85160-80-1; 85160-81-2 Role: RCT (Reactant), RACT (Reactant or reagent) (storage and use as Wittig reagents with aldehydes, ketones, and formates)
REVIEWED